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Premise Across taxa, vegetative and floral traits that vary along a fast-slow life-history axis are often correlated with leaf functional traits arrayed along the leaf economics spectrum, suggesting a constrained set of adaptive trait combinations. Such broad-scale convergence may arise from genetic constraints imposed by pleiotropy (or tight linkage) within species, or from natural selection alone. Understanding the genetic basis of trait syndromes and their components is key to distinguishing these alternatives and predicting evolution in novel environments. Methods We used a line-cross approach and quantitative trait locus (QTL) mapping to characterize the genetic basis of twenty leaf functional/physiological, life history, and floral traits in hybrids between annualized and perennial populations of scarlet monkeyflower (Mimulus cardinalis). Results We mapped both single and multi-trait QTLs for life history, leaf function and reproductive traits, but found no evidence of genetic co-ordination across categories. A major QTL for three leaf functional traits (thickness, photosynthetic rate, and stomatal resistance) suggests that a simple shift in leaf anatomy may be key to adaptation to seasonally dry habitats. Conclusions Our results suggest that the co-ordination of resource-acquisitive leaf physiological traits with a fast life-history and more selfing mating system results from environmental selection rather than functional or genetic constraint. Independent assortment of distinct trait modules, as well as a simple genetic basis to leaf physiological traits associated with drought escape, may facilitate adaptation to changing climates.

The influence of human harvest on evolution of secondary sexual characteristics has implications for sustainable management of wildlife populations. The phenotypic consequences of selectively removing males with large horns or antlers from ungulate populations have been a topic of heightened concern in recent years. Harvest can affect size of horn‐like structures in two ways: (a) shifting age structure toward younger age classes, which can reduce the mean size of horn‐like structures, or (b) selecting against genes that produce large, fast‐growing males. We evaluated effects of age, climatic and forage conditions, and metrics of harvest on horn size and growth of mountain sheep (Ovis canadensis ssp.) in 72 hunt areas across North America from 1981 to 2016. In 50% of hunt areas, changes in mean horn size during the study period were related to changes in age structure of harvested sheep. Environmental conditions explained directional changes in horn growth in 28% of hunt areas, 7% of which did not exhibit change before accounting for effects of the environment. After accounting for age and environment, horn size of mountain sheep was stable or increasing in the majority (~78%) of hunt areas. Age‐specific horn size declined in 44% of hunt areas where harvest was regulated solely by morphological criteria, which supports the notion that harvest practices that are simultaneously selective and intensive might lead to changes in horn growth. Nevertheless, phenotypic consequences are not a foregone conclusion in the face of selective harvest; over half of the hunt areas with highly selective and intensive harvest did not exhibit age‐specific declines in horn size. Our results demonstrate that while harvest regimes are an important consideration, horn growth of harvested male mountain sheep has remained largely stable, indicating that changes in horn growth patterns are an unlikely consequence of harvest across most of North America.

While the fundamental biophysics of C 3 photosynthesis is highly conserved across plants, substantial leaf structural and enzymatic variation translates into variability in rates of carbon assimilation. Although this variation is well documented, it remains poorly understood how photosynthetic rates evolve, and whether macroevolutionary changes are related to the evolution of leaf morphology and biochemistry. A substantial challenge in large-scale comparative studies is disentangling evolutionary adaptation from environmental acclimation. We overcome this by using a ‘macroevolutionary common garden’ approach in which we measured metabolic traits ( J max and V cmax ) from 111 phylogenetically diverse species in a shared environment. We find substantial phylogenetic signal in these traits at moderate phylogenetic timescales, but this signal dissipates quickly at deeper scales. Morphological traits exhibit phylogenetic signal over much deeper timescales, suggesting that these are less evolutionarily constrained than metabolic traits. Furthermore, while morphological and biochemical traits (LMA, N area and C area ) are weakly predictive of J max and V c max , evolutionary changes in these traits are mostly decoupled from changes in metabolic traits. This lack of tight evolutionary coupling implies that it may be incorrect to use changes in these functional traits in response to global change to infer that photosynthetic strategy is also evolving.

PREMISEAcross taxa, vegetative and floral traits that vary along a fast-slow life-history axis are often correlated with leaf functional traits arrayed along the leaf economics spectrum, suggesting a constrained set of adaptive trait combinations. Such broad-scale convergence may arise from genetic constraints imposed by pleiotropy (or tight linkage) within species, or from natural selection alone. Understanding the genetic basis of trait syndromes and their components is key to distinguishing these alternatives and predicting evolution in novel environments.METHODSWe used a line-cross approach and quantitative trait locus (QTL) mapping to characterize the genetic basis of twenty leaf functional/physiological, life history, and floral traits in hybrids between annualized and perennial populations of scarlet monkeyflower (Mimulus cardinalis).RESULTSWe mapped both single and multi-trait QTLs for life history, leaf function and reproductive traits, but found no evidence of genetic co-ordination across categories. A major QTL for three leaf functional traits (thickness, photosynthetic rate, and stomatal resistance) suggests that a simple shift in leaf anatomy may be key to adaptation to seasonally dry habitats.CONCLUSIONSOur results suggest that the co-ordination of resource-acquisitive leaf physiological traits with a fast life history and more selfing mating system results from environmental selection rather than functional or genetic constraint. Independent assortment of distinct trait modules, as well as a simple genetic basis to leaf physiological traits associated with drought escape, may facilitate adaptation to changing climates.

Trait integration arises through both selection on functional coordination and shared developmental pathways. Different anatomical components must both work well and develop together to generate individuals with the appropriate physiology to survive and reproduce in their environment. In this study, we used a common garden experiment and Bayesian multilevel models to test whether stomatal anatomy coordinates leaf gas exchange, Rubisco kinetics, and leaf size across 10 closely related species of Limonium from the Balearic Islands. The results indicate that the anatomical determinants of maximum stomatal conductance, stomatal density and size, were functionally coordinated with Rubisco kinetics – species whose stomatal anatomy was correlated with low stomatal conductance have evolved Rubisco enzymes better adapted to low operational chloroplastic CO2 concentrations. Lower stomatal density was associated with greater leaf size, which can be explained by a greater proportion of pavement cells in large-leaved species. These results suggest that both selection for functional coordination (stomata and Rubisco kinetics) and shared development pathways (stomatal density and leaf area) likely shape patterns of trait integration between species.

The genus Mimulus is a well-studied group of plant species, which has for decades allowed researchers to address a wide array of fundamental questions in biology (Wu & al. 2008; Twyford & al. 2015). Linnaeus named the type species of Mimulus (ringens L.), while Darwin (1876) used Mimulus (luteus L.) to answer key research questions. The incredible phenotypic diversity of this group has made it the focus of ecological and evolutionary study since the mid-20th century, initiated by the influential work of Clausen, Keck, and Hiesey as well as their students and collaborators (Clausen & Hiesey 1958; Hiesey & al. 1971, Vickery 1952, 1978). Research has continued on this group of diverse taxa throughout the 20th and into the 21st century (Bradshaw & al. 1995; Schemske & Bradshaw 1999; Wu & al. 2008; Twyford & al. 2015; Yuan 2019), and Mimulus guttatus was one of the first non-model plants to be selected for full genome sequencing (Hellsten & al. 2013). Mimulus has played a key role in advancing our general understanding of the evolution of pollinator shifts (Bradshaw & Schemske 2003; Cooley & al. 2011; Byers & al. 2014), adaptation (Lowry & Willis 2010; Kooyers & al. 2015; Peterson & al. 2016; Ferris & Willis 2018; Troth & al. 2018), speciation (Ramsey & al. 2003; Wright & al. 2013; Sobel & Streisfeld 2015; Zuellig & Sweigart 2018), meiotic drive (Fishman & Saunders 2008), polyploidy (Vallejo-Marín 2012; Vallejo-Marín & al. 2015), range limits (Angert 2009; Sexton et al. 2011; Grossenbacher & al. 2014; Sheth & Angert 2014), circadian rhythms (Greenham & al. 2017), genetic recombination (Hellsten & al. 2013), mating systems (Fenster & Ritland 1994; Dudash & Carr 1998; Brandvain & al. 2014) and developmental biology (Moody & al. 1999; Baker & al. 2011, 2012; Yuan 2019). This combination of a rich history of study coupled with sustained modern research activity is unparalleled among angiosperms. Across many interested parties, the name Mimulus therefore takes on tremendous biological significance and is recognizable not only by botanists, but also by zoologists, horticulturalists, naturalists, and members of the biomedical community. Names associated with a taxonomic group of this prominence should have substantial inertia, and disruptive name changes should be avoided. As members of the Mimulus community, we advocate retaining the genus name Mimulus to describe all monkeyflowers. This is despite recent nomenclature changes that have led to a renaming of most monkeyflower species to other genera.

Climate can affect plant populations through direct effects on physiology and fitness, and through indirect effects on their relationships with pollinating mutualists. We therefore expect that geographic variation in climate might lead to variation in plant mating systems. Biogeographic processes, such as range expansion, can also contribute to geographic patterns in mating system traits. We manipulated pollinator access to plants in eight sites spanning the geographic range of Clarkia pulchella to investigate geographic and climatic drivers of fruit production and seed set in the absence of pollinators (reproductive assurance). We examined how reproductive assurance and fruit production varied with the position of sites within the range of the species and with temperature and precipitation. We found that reproductive assurance in C. pulchella was greatest in populations in the northern part of the species’ range and was not well explained by any of the climate variables that we considered. In the absence of pollinators, some populations of C. pulchella have the capacity to increase fruit production, perhaps through resource reallocation, but this response is climate dependent. Pollinators are important for reproduction in this species, and recruitment is sensitive to seed input. The degree of autonomous self-pollination that is possible in populations of this mixed-mating species may be shaped by historic biogeographic processes or variation in plant and pollinator community composition rather than variation in climate.

Climate can affect plant populations through direct effects on physiology and fitness, and through indirect effects on their relationships with pollinating mutualists. We therefore expect that geographic variation in climate might lead to variation in plant mating systems. Biogeographic processes, such as range expansion, can also contribute to geographic patterns in mating system traits. We manipulated pollinator access to plants in eight sites spanning the geographic range of Clarkia pulchella to investigate geographic and climatic drivers of fruit production and seed set in the absence of pollinators (reproductive assurance). We examined how reproductive assurance and fruit production varied with the position of sites within the range of the species and with temperature and precipitation. We found that reproductive assurance in C. pulchella was greatest in populations in the northern part of the species’ range, and was not well-explained by any of the climate variables that we considered. In the absence of pollinators, some populations of C. pulchella have the capacity to increase fruit production, perhaps through resource reallocation, but this response is climate-dependent. Pollinators are important for reproduction in this species, and recruitment is sensitive to seed input. The degree of autonomous self-pollination that is possible in populations of this mixed-mating species may be shaped by historic biogeographic processes or variation in plant and pollinator community composition rather than variation in climate.

Local adaptation is commonly observed in nature: organisms perform well in their natal environment, but poorly outside it. Correlations between traits and latitude, or latitudinal clines, are among the most common pieces of evidence for local adaptation, but identifying the traits under selection and the selective agents is challenging. Here, we investigated a latitudinal cline in growth and photosynthesis across 16 populations of the perennial herbErythranthe cardinalis(Phrymaceae). Using machine learning methods, we identify interannual variation in precipitation as a likely selective agent: Southern populations from more variable environments had higher photosynthetic rates and grew faster. We hypothesize that selection may favor a more annualized life history – grow now rather than save for next year – in environments where severe droughts occur more often. Thus our study provides insight into how species may adapt if Mediterranean climates become more variable due to climate change.

In recent years, returns of adult sockeye salmon Oncorhynchus nerka to the Columbia River Basin have reached numbers not observed since the 1950s. To understand factors related to these increased returns, we first looked for changes in freshwater production and survival of juvenile migrants. We then evaluated productivity changes by estimating smolt-to-adult return rates (SAR) for juvenile migration years 1985–2010. We found SAR varied between 0.2 and 23.5%, with the highest values coinciding with recent large adult returns. However, the largest adult return, in 2012, resulted not from increased survival, but from increased smolt production. We evaluated 19 different variables that could influence SARs, representing different facets of freshwater and ocean conditions. We used model selection criteria based on small-sample corrected AIC to evaluate the relative performance of all two- and three-variable models. The model with April upwelling, Pacific Northwest Index (PNI) in the migration year, and PNI in the year before migration had 10 times the AICc weight as the second-best-supported model, and R2 = 0.82. The variables of April ocean upwelling and PNI in the migration year had high weights of 0.996 and 0.927, respectively, indicating they were by far the best of the candidate variables to explain variations in SAR. While our analyses were primarily correlative and limited by the type and amount of data currently available, changes in ocean conditions in the northern California Current system, as captured by April upwelling and PNI, appeared to play a large role in the variability of SAR.

Natural selection on photosynthetic performance is a primary factor determining leaf phenotypes. The complex CO2 diffusion path from substomatal cavities to the chloroplasts – the mesophyll conductance (gm) – limits photosynthetic rate in many species and hence shapes variation in leaf morphology and anatomy. Among sclerophyllous and succulent taxa, structural investment in leaves, measured as the leaf dry mass per area (LMA), has been implicated in decreased gm. However, in herbaceous taxa with high gm, it is less certain how LMA impacts CO2 diffusion and whether it significantly affects photosynthetic performance. We addressed these questions in the context of understanding the ecophysiological significance of leaf trait variation in wild tomatoes, a closely related group of herbaceous perennials. Although gm was high in wild tomatoes, variation in gm significantly affected photosynthesis. Even in these tender-leaved herbaceous species, greater LMA led to reduced gm. This relationship between gm and LMA is partially mediated by cell packing and leaf thickness, although amphistomy (equal distribution of stomata on both sides of the leaf) mitigates the effect of leaf thickness. Understanding the costs of increased LMA will inform future work on the adaptive significance of leaf trait variation across ecological gradients in wild tomatoes and other systems.

Adult leaf fenestration in "Swiss cheese" plants (Monstera Adans.) is an unusual leaf shape trait lacking a convincing evolutionary explanation. Monstera are secondary hemiepiphytes that inhabit the understory of tropical rainforests, where photosynthesis from sunflecks often makes up a large proportion of daily carbon assimilation. Here I present a simple model of leaf-level photosynthesis and whole-plant canopy dynamics in a stochastic light environment. The model demonstrates that leaf fenestration can reduce the variance in plant growth and thereby increase geometric mean fitness. This growth-variance hypothesis also suggests explanations for conspicuous ontogenetic changes in leaf morphology (heteroblasty) in Monstera, as well as the absence of leaf fenestration in co-occurring juvenile tree species. The model provides a testable hypothesis of the adaptive significance of a unique leaf shape and illustrates how variance in growth rate could be an important factor shaping plant morphology and physiology.

Nearshore marine environments are influenced by an array of variables that can either be land-derived or of marine origin, and nearshore phytoplankton communities may differ in their taxonomic composition and biomass in response to such variables. The KwaZulu-Natal Bight (hereafter referred to as ‘the bight’) is an oligo-mesotrophic, nearshore oceanic environment, that is influenced by both terrestrial run-off and upwelling. A microphytoplankton survey of the bight conducted over several stations and depths and two seasons was conducted in order to ascertain species composition, abundance and biomass. Microphytoplankton abundance was generally low (a maximum of 180 000 cells l–1 was recorded) but differed considerably between sites and seasons. A total of 99 taxa of mainly Bacillariophyceae and some Dinophyceae, Prymnesiophyceae and Cyanophyceae were identified in the present study. In the central bight, higher abundance and biomass were measured in February (wet season), which may be a possible consequence of terrestrial nutrient inputs. In the northern and southern bight we measured higher abundance and biomass in August (dry season). Upwelling was not detected during the study, but an influence of terrestrial nutrient sources was detected at the coastal stations. Turbid conditions were specific to the site near the Thukela River mouth and possibly influenced abundance, biomass and species composition at this site. Historic data on microphytoplankton composition are scarce, but comparisons with surveys from the 1960s reveal that around 60% of the common diatoms recorded then also occurred in the present study. Small taxa [20–200 μm] dominated the microphytoplankton community. Community composition was fairly uniform throughout the bight in both seasons, dominated in general by Chaetoceros species, and on occasion co-dominated by Thalassionema nitzschioides and Dactyliosolen fragilissimus.Keywords: Agulhas current, diatoms, phytoplankton, primary productivity, run-off, upwelling

Studies of resource selection form the basis for much of our understanding of wildlife habitat requirements, and resource selection functions (RSFs), which predict relative probability of use, have been proposed as a unifying concept for analysis and interpretation of wildlife habitat data. Logistic regression that contrasts used and available or unused resource units is one of the most common analyses for developing RSFs. Recently, resource utilization functions (RUFs) have been developed, which also predict probability of use. Unlike RSFs, however, RUFs are based on a continuous metric of space use summarized by a utilization distribution. Although both RSFs and RUFs predict space use, a direct comparison of these 2 modeling approaches is lacking. We compared performance of RSFs and RUFs by applying both approaches to location data for 75 Rocky Mountain elk (Cervus elaphus) and 39 mule deer (Odocoileus hemionus) collected at the Starkey Experimental Forest and Range in northeastern Oregon, USA. We evaluated differences in maps of predicted probability of use, relative ranking of habitat variables, and predictive power between the 2 models. For elk, 3 habitat variables were statistically significant (P < 0.05) in the RSF, whereas 7 variables were significant in the RUF. Maps of predicted probability of use differed substantially between the 2 models for elk, as did the relative ranking of habitat variables. For mule deer, 4 variables were significant in the RSF, whereas 6 were significant in the RUF, and maps of predicted probability of use were similar between models. In addition, distance to water was the top-ranked variable in both models for mule deer. Although space use by both species was predicted most accurately by the RSF based on cross-validation, differences in predictive power between models were more substantial for elk than mule deer. To maximize accuracy and utility of predictive wildlife-habitat models, managers must be aware of the relative strengths and weaknesses of different modeling techniques. We conclude that although RUFs represent a substantial advance in resource selection theory, techniques available for generating RUFs remain underdeveloped and, as a result, RUFs sometimes predict less accurately than models derived using more conventional techniques.

Lotus species collec ted from a range of geographical locations were evaluated for relationships between plant habit and size, leaf proanthocyanidin (PA) content, flower colour, stem colour, leaf colour, trichome density, and geographic origin. No relationships occurred between leaf PA concentration and morphological trait or collection site. Trichome coverage was moderately correlated with plant size (r = -0.70). Several accessions, e.g., L. angustissimus L. and L. castellanis Boiss. & Reut., consisted of small, trichome-covered plants distinct from the large, glabrous plants typical of the model species L. corniculatus var. japonicus ecotype Gifu B129. These two morphology types were also represented among the tan mutants of Gifu B129. Due to the importance of trichomes and PA in plant defence, PA composition was compared between L. angustissimusand tan1 (both representing the small trichome-covered phenotype) and ecotype Gifu B129 and tan2 (both representing the large, glabrous phenotype). Both the tan1 and tan2 mutants accumulated substantial amounts of leaf PA similar in size to the small oligomers recovered from leaves of L. angustissimus. PA polymers were undetectable in Gifu B129 leaves, while floral PA extracts of this ecotype included a much larger PA polymer. Flavonoid composition in leaves of tan1 and L. angustissimus was complex, and differed from the simple profile in Gifu B129 leaves. Key words: Lotus, proanthocyanidin, flavonoids, trichomes, morphology, plant habit, variability

Are organisms free to reach their adaptive optima or constrained by hard-wired developmental programs? Recent evidence suggests that the arrangement of stomata on abaxial (lower) and adaxial (upper) leaf surfaces may be an important adaptation in plants, but stomatal traits on each surface likely share developmental pathways that could hamper evolution. We reviewed the quantitative genetics of stomatal density to look for loci that (1) affected ab- or adaxial density independently or (2) pleiotropically affected stomatal density on both surfaces. We also used phylogenetic comparative methods to test for independent versus correlated evolution of stomatal traits (density, size, and pore index) on each surface from 14 amphistomatous wild tomato taxa (Solanum; Solanaceae). Naturally occurring and laboratory-induced genetic variation alters stomatal density on one surface without affecting the other, indicating that development does not strongly constrain the spectrum of available mutations. Among wild tomato taxa, traits most closely related to function (stomatal pore index and density) evolved independently on each surface, whereas stomatal size was constrained by correlated evolution. Genetics and phylogenetics demonstrate mostly independent evolution of stomatal function on each leaf surface, facilitating largely unfettered access to fitness optima.

Past research indicates that on an annual basis, smolts of stream-type Chinook salmon Oncorhynchus tshawytscha collected at Snake River dams and transported by barge to below Bonneville Dam have greater post-hydropower system mortality than smolts that migrate in-river. To date, this difference has most commonly been attributed to stress from collection and transportation, leading to decreased disease resistance or predator avoidance ability. Using both hatchery and wild passive integrated transponder (PIT) tagged Chinook salmon, we explored two mechanisms that either separately or jointly contributed to an alternative explanation: Altered timing of ocean entry and lost growth opportunity leading to size-selective predation. Based on weekly estimates of in-river survival and adult return rates of smolts that were transported or that migrated in-river between Lower Granite and Bonneville dams, we found greater post-hydropower system mortality for smolts transported early in the season but greater ...

Flaxseed (Linum usitatissimum L.) is a major source of dietary intake of lignans by virtue of the high concentrations (0.71.5) that are present in the seed. The principal lignan present in flaxseed is secoisolariciresinol diglucoside (SDG), which occurs as a component of a linear ester-linked complex in which the C6-OH of the glucose of SDG is esterified to the carboxylic acid of hydroxymethylglutaric acid. Also present in flaxseed and in resulting lignan extracts are significant quantities of 2 cinnamic acid glycosides. Our emerging understanding of the biological activity of flax lignans is based on studies using a variety of materials ranging from whole ground seed to pure SDG. The underlying assumption of most of these studies is that the biological activity of flax lignans results from their conversion to the mammalian lignans enterolactone (EL) and enterodiol (ED). There are, however, several intermediate compounds generated during the digestion and metabolism of flax lignans, including SDG and its aglycones and secoisolariciresinol (Seco), that are good candidates to be the principal bioactive molecule. This review will document the history of the development of lignan analytical methods and illustrate how analytical methods have influenced the interpretation of animal and human trials and our understanding of the biological activity of flax lignans.

To identify simple screening tools for selecting condensed tannin (CT)-containing forages as candidate sources for further study, CT were isolated from nine legumes, and their molecular weights (MW), chromophore production, capacity to precipitate bovine serum albumin (BSA) and Fraction 1 protein (Rubisco) isolated from alfalfa, and inhibition of filter paper digestion were compared. Sources were as follows: leaves of sericea lespedeza (Lespedeza cuneata Dum.-Cours.), crown vetch (Coronilla varia L.), and sainfoin (Onobrychis viciifolia Scop.); stems of hedysarum (Hedysarum alpinum L.); seeds of alfalfa (Medicago sativa L.); and whole plants of birdsfoot trefoil (Lotus corniculatus var. corniculatus L.) and three varieties of big trefoil (Lotus pedunculatus Cav.), viz., Lotus uliginosus Schkuhr, L. uliginosus var. glabriusculus, and L. uliginosus var. villosus. Molecular weights and sizes (degrees of polymerization) of the CT varied considerably within and among plant species. Average MW ranged from 3036 Da (crown vetch) to 7143 Da (lespedeza). All CT exhibited greater capacity (w/w basis) to bind alfalfa Rubisco than BSA. Relative astringencies (microg CT required to precipitate 1 mg protein) against BSA ranged from 262.5 for CT from lespedeza to 435.5 for CT from L. corniculatus, and against Rubisco, from 49.6 (sainfoin) to 108.2 (alfalfa seed). Including CT at 300 microg/ml in cultures of Fibrobacter succinogenes reduced digestion of cellulose filter paper by 19.8% (sainfoin) to 92.4% (crown vetch) and increased the specific activity of cell-associated endoglucanase. There were no correlations between inhibitory effects of CT on filter paper digestion and (1) chromophore formation during CT assay by butanol-HCl, vanillin-HCl, or H2SO4; (2) precipitation of BSA or alfalfa Rubisco; and (3) MW of CT. The most inhibitory CT for cellulose digestion included those with broad and with narrow MW distributions. Sainfoin was the most desirable source of CT, as it had the highest capacity to bind alfalfa protein and was least inhibitory to cellulose digestion by F. succinogenes. This study suggests that these properties are not easily defined via chemical means, and that biological assays using rumen bacteria may help identify those CT with properties of nutritional interest.

Lignans have been part of both diet and herbal medicines for centuries. It is only in the last half century that phytochemists have described the structures of the lignans. Pharmacologists have only become interested in the biological activity of lignans in the last few decades. Much of the early interest focused on podophyllotoxin type lignans and their derivatives. Recent literature has recorded very many new lignans or lignan derivatives with a diverse range of biological activities. In 1955, the isolation from flax seed and the structure of the lignan derivative secoisolariciresinol diglucoside (SDG) was reported. Possible biological activity of SDG, and the mammalian lignan metabolites, enterolactone and enterodiol, was initially reported about 20 years later. During the next 30 years, there has been extensive research on the biological effects of both flax seed and rye lignans since both are metabolized into the mammalian lignans. Research on the activity of lignans on breast, colon, prostate and thyroid cancer has generally shown beneficial effects although there are some studies with either no conclusive or negative effect. Lignans have been shown to have positive effects in lowering relative risk factors for heart disease. Use of flax seed or SDG has been shown to have positive effects in both lupus and polycystic kidney disease models. Studies of both type I and II diabetes models have reported positive results when using SDG. Flax seed has also been reported to be hepatoprotective. Reproductive effects have been observed with flax seed or SDG and have been found to be dose and time related. There are many possible mechanistic explanations for the observed bioactivities including involvement in hormonal metabolism or availability, angiogenesis, anti-oxidation and gene suppression. Abbreviations: ALA – alpha linolenic acid; ApcMin – adenomatous polyposis coli multiple intestinal neoplasia; BBdp – BioBreeding diabetic prone; CCl4– carbon tetrachloride; CDC – Crop Development Centre; CHD – cardiovascular heart disease; DMBA – dimethylbenzanthracene; DNA – deoxyribonucleic acid; ER – estrogen receptor; λGT –γ-glutamyltranspeptidase; HDL – high-density lipoprotein; HMGA – hydroxymethyl glutaric acid; IDDM – insulin dependent diabetes mellitus; LDL – low-density lipoprotein; MRL/lpr, Murine Lupus/lymphoproliferative; MDA – malondiadehyde; NIDDM – non-insulin dependent diabetes mellitus; ORF – oxygen free radical; PAF – platelet activating factor; PKD – Polycystic kidney disease; PEPCK – phosphoenolpyruvate carboxykinase; PMNL – polymorphonuclear monocytes; STZ – streptozoticin; TC – total cholesterol; TG – triglycerides; SDG – secoisolariciresinol diglucoside; ZDF – Zucker diabetic fatty.

From 1995 to 2000, subyearling fall chinook salmon Oncorhynchus tshawytscha reared at Lyons Ferry Hatchery were PIT-tagged at the hatchery, trucked upstream, acclimated, and released into free-flowing sections of the Snake River weekly from early June to mid-July. We estimated survival probabilities and travel time through the lower Snake River and detection probabilities at dams for each weekly release group. The average median time between release and arrival at Lower Granite Dam was 43.5 d. For each group, we split this time into two nearly equal (on average) periods: one when most fish in the group were rearing and one when most fish had apparently begun active seaward migration. The estimated survival for hatchery fish from release to the tailrace of Lower Granite Dam decreased with release date each year. The estimated survival through this reach was significantly correlated with three environmental variables: survival decreased as discharge (“flow”) decreased, as water transparency increas...

A study was conducted to compare the travel times, detection probabilities, and survival of migrant hatchery-reared yearling chinook salmon Oncorhynchus tshawytscha tagged with either gastrically or surgically implanted sham radio tags (with an imbedded passive integrated transponder (PIT) tag) with those of their cohorts tagged only with PIT tags in the Snake and Columbia rivers. Juvenile chinook salmon with gastrically implanted radio tags migrated significantly faster than either surgically radio-tagged or PIT-tagged fish, while migration rates were similar among surgically radio-tagged and PIT-tagged fish. The probabilities of PIT tag detection at downstream dams varied by less than 5% and were not significantly different among the three groups. Survival was similar among treatments for median travel times of less than approximately 6 d (migration distance of 106 km). However, for both gastrically and surgically radio-tagged fish, survival was significantly less than for PIT-tagged fish, for ...

Simple and multiple linear regressions were used to evaluate factors associated with travel time and survival of yearling chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss migrating in the lower Snake River. Factors were release date and environmental variables measuring river discharge (flow), water temperature, and the percentage of total flow passed over spillways at dams. Data were collected from migrant salmonids tagged with passive integrated transponder (PIT) tags from 1995 through 1999. The greatest distance over which survival could be estimated during all 5 years was from the Lower Granite Dam tailrace to the McNary Dam tailrace (225 river km encompassing four dams and reservoirs). Release groups consisted of PIT-tagged fish leaving Lower Granite Dam daily. Data from more than 451,000 PIT-tagged yearling chinook salmon and 204,000 PIT-tagged steelhead were analyzed. For each daily group, indices of exposure to environmental factors were calculated as the average value for ...

Adaptive evolution requires both raw genetic material and an accessible path of high fitness from one fitness peak to another. In this study, we used an introgression line (IL) population to map quantitative trait loci (QTL) for leaf traits thought to be associated with adaptation to precipitation in wild tomatoes (Solanum sect. Lycopersicon; Solanaceae). A QTL sign test showed that several traits likely evolved under directional natural selection. Leaf traits correlated across species do not share a common genetic basis, consistent with a scenario in which selection maintains trait covariation unconstrained by pleiotropy or linkage disequilibrium. Two large effect QTL for stomatal distribution colocalized with key genes in the stomatal development pathway, suggesting promising candidates for the molecular bases of adaptation in these species. Furthermore, macroevolutionary transitions between vastly different stomatal distributions may not be constrained when such large-effect mutations are available. Finally, genetic correlations between stomatal traits measured in this study and data on carbon isotope discrimination from the same ILs support a functional hypothesis that the distribution of stomata affects the resistance to CO2 diffusion inside the leaf, a trait implicated in climatic adaptation in wild tomatoes. Along with evidence from previous comparative and experimental studies, this analysis indicates that leaf traits are an important component of climatic niche adaptation in wild tomatoes and demonstrates that some trait transitions between species could have involved few, large-effect genetic changes, allowing rapid responses to new environmental conditions.

Worldwide, persistent cyanobacterial blooms are becoming more frequent and are often associated with effects of global climate change. In June 2009, a widespread bloom of the unicellular cyanobacterium, Cyanothece sp., appeared in North Lake and False Bay of Lake St Lucia – a large (360 km2) estuarine lake system in KwaZulu-Natal, South Africa – and persisted for 18 months. It remains unclear how the bloom status was maintained for so long. This study investigates aspects of the nutrient uptake dynamics of Cyanothece sp. and how this process may relate to maintaining a persistent bloom state during hypersaline conditions. 15N nutrient uptake experiments were performed to evaluate the effect of the most important environmental variables on the nutrient uptake rate of Cyanothece sp. Highest 15N uptake rates were during salinities of 35 and temperatures of 30 °C for both N sources (43.9 [SE 18.3] and 85.5 [SE 42.9] μg atom N l–1 h–1 for 15NH4+ and 15NO3 − respectively). In contrast, at high salinities of 160 and low temperatures of 10 °C, 15NH4 + and 15NO3− uptake rates were low (3.76 [SE 0.23] and 14.5 [SE 6.40] μg atom N l–1 h–1 respectively). Hence nutrient uptake was significantly influenced by environmental variables, particularly salinity, which suppressed uptake rates, and temperature, which facilitated them. The long-term bloom maintenance appears to be attributed to efficient nutrient uptake rates, absence of grazers during the hypersaline phase, and the ability of Cyanothece sp. to outcompete other microalgae at temperatures >25 °C.Keywords: 15N isotope pairing technique, cyanobacteria, estuarine lake, hypersalinity, iSimangaliso, unicellularAfrican Journal of Marine Science 2014, 36(2): 155–161

E. WHITLEY, D. MUIR and W.M. WAITES.2000. The effect of Modified Atmosphere Packaging (MAP) on the growth of Listeria monocytogenes in mould ripened cheeses was studied at refrigeration temperatures (2–8·3 °C) over a storage period of 6 weeks. Control experiments in cling film with no atmospheric modification produced a lag time before growth of up to 1 week and rapid subsequent growth. MAP with a CO2 concentration of less than 20% allowed growth to occur but when O2 was incorporated; the lag time was reduced from 3 to 2 weeks and subsequent growth was also faster, producing an increase in cell numbers of 1·4 log cycles over the incubation period. N2–MAP in the absence of O2 increased the lag time to 3 weeks and slowed growth, while the inclusion of CO2 extended the lag to 3 weeks and slowed subsequent growth even more. In MAP with 80:10:10 (v/v/v) N2:CO2:O2, there was a lag period of 2–3 weeks before growth of L. monocytogenes occurred, while the total viable aerobic count (TVAC) decreased by 2–3 log cycles and the total Lactobacillus count showed little change. It was concluded that MAP was not suitable for preventing the growth of L. monocytogenes in such cheeses.

Precise, up-to-date survival estimates for salmonids that migrate through reservoirs, hydroelectric dams, and free-flowing sections of the Snake and Columbia rivers are essential to develop effective strategies for recovering depressed stocks. To provide this information, survival was estimated for yearling chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss with passive integrated transponder (PIT) tags that migrated through Snake River dams and reservoirs from 1993 through 1998. A multiple-recapture model for single release groups was used to estimate survival from detections of PIT-tagged fish at dams. The stretch of river over which survival was estimated varied between years, depending on the release site, the number of dams with the capability to detect and rerelease PIT-tagged fish back to the river, the total number of fish marked, and the efficiency of detecting PIT-tagged fish at each dam. Precision of survival estimates varied with the number of fish PIT-tagged and released...

This paper examines average annual survival of juvenile spring–summer chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss during migration through the hydropower system of the Snake and Columbia rivers from 1966 to 1980 and 1993 to 1999. In each year, survival was estimated from observations of marked fish in a portion of the hydropower system corridor. We expanded these estimates to calculate an annual estimate of survival over the entire system (head of uppermost reservoir to tailrace of lowermost dam). Temporal changes in the hydropower system were compared with trends in estimated survival to evaluate the effects of dams on survival of downstream migrants. When only four dams were in place (1966–1967), estimates of survival through the hydropower system were 32–56%. Four additional dams were constructed between 1968 and 1975. Survival estimates during the 1970s typically were 10–30% for spring–summer chinook salmon, but less than 3% in the drought years of 1973 and 1977. From 1993...

Using yearling chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss tagged with passive integrated transponders (PITs), we estimated passage survival through bypass systems, turbines, and spill bays with and without flow deflectors at Snake River dams relative to survival of fish released into the tailrace below the dam. Actively migrating fish were collected and marked with PIT tags at Snake River dam smolt collection facilities. Groups of tagged fish were then released through hoses into different passage routes; releases were coincident with a tailrace release approximately 1–2 km below the dam. Relative survival was estimated by the use of tag–recapture models for paired releases from detections of individual PIT-tagged fish at juvenile collection or detection facilities at downstream dams. Detection sites included Little Goose, Lower Monumental, McNary, John Day, and Bonneville dams, depending on the release location and year. Standard errors of relative survival probability estim...

An outbreak of pulmonary abscessation due to the common environmental fungus Paecilomyces variotii occurred in a colony of gp91 phox−/− mice, which lack functional NADPH oxidase, the enzyme complex responsible for generating the respiratory burst in phagocytes. Parenchyma surrounding the abscesses showed intense acidophilic macrophage pneumonia, and similar but much milder lesions were present in each of 24 gp91 phox−/− mice free from other pulmonary lesions. These findings indicate a high prevalence of acidophilic macrophage pneumonia in gp91 phox−/− mice, or at least in this particular stock. The presence of this lesion may complicate studies in which phagocyte-dependent pulmonary defence plays a significant role.

Two experiments each with two rates of feeding (maintenance and twice maintenance) were conducted during summer 1993/94 (Expt 1) and summer 1994/95 (Expt 2), at Massey University, New Zealand. Four sambar and four red deer, including stags and hinds aged 10–14 months, were used in each year. Animals were fed a pelleted diet (total N 30 g/kg DM; NDF 247 g/kg DM). Digestibility and nitrogen (N) balances were determined using deer metabolism cages, whilst methane production and heat production were determined using open circuit respiration calorimetry, with measurements made on each deer at both rates of feeding. Digestibility and metabolizability of energy were greater for sambar than for red deer in Expt 1 but not in Expt 2. Nitrogen retention, expressed as a proportion of N intake, was similar for sambar and red deer. Metabolizable energy required for maintenance (MEm) was 474 kJ kg W−0·75 d−1 for sambar deer and 567 kJ kg W−0·75 d−1 for red deer, whilst the efficiency of utilization of ME above maintenance (kg) was similar for sambar deer and red deer. These studies indicated that the sambar deer had lower rates of maintenance heat production than the red deer, which may explain the sambar's superior feed conversion measured in previous experiments. However, the two species utilized nitrogen with similar efficiency, when fed a high quality ration.

The artificial insemination of 400 red deer hinds with sambar deer semen resulted in 31 pregnancies at day 40 (24 at day 100) and the birth of four calves. Only one female calf was born alive. The artificial insemination of 10 sambar deer hinds with red deer semen resulted in five pregnancies at day 40, of which none went to term. Gel electrophoresis of three blood proteins confirmed the live calf as the first documented sambar deer x red deer hydrid. G-banded karyotypes were consistent with the calf (2n = 62; six unpaired and one paired metacentric autosomes) being the offspring of a red deer dam (2n = 68; single pair of metacentric autosomes) and a sambar deer sire (2n = 56; seven pairs of metacentric autosomes).

A subcellular enzyme fraction (Mr>20 × 106) from immature sainfoin leaves catalysed the two-step NADPH-dependent reduction of ( + )-dihydromyricetin to ( + )-gallocatechin. No enzyme-mediated (−)-epigallocatechin was formed under the conditions employed, and only traces of 2R,3S-trans-3S,4S-cis-leucodelphinidin were observed. The two-step reductase activity mirrored proanthocyanidin content, rising to a maximum before leaflet unfolding, then declining during leaf expansion. When [14C]( + )-dihydromyricetin and [C4-3H]2R,3S-trans-3S,4S-cis-leucodelphinidin were supplied to the same fraction, preferential utilization of ( + )-dihydromyricetin was observed. Enzymic formation of proanthocyanidin dimers could not be detected using these preparations under a variety of conditions. However, a small portion of radioactivity was bound to the subcellular fraction after addition of labelled ( + )-catechin. In addition, in vivo incorporation of ( + )-dihydromyricetin into proanthocyanidins was observed.

A Gram-positive unicellular coccal-diphtheroid rod causing foam in an activated sludge plant was successfully isolated by micromanipulation. Phenotypic characterization and 16S rDNA sequencing identified it as Nocardia farcinica. This is the first report that this opportunistic pathogen is a foam-causing bacterium in activated sludge, and the clinical implications of these observations are discussed.

The reflective materials in the iris stroma of bright-irised American blackbirds (Icterinae, Emberizidae) and the red-eyed vireo (vireo olivaceus) (Vireonidae) were characterized using high-performance liquid chromatography (HPLC) and diode-array detection. Two purines, guanine and hypoxanthine, and two pteridines, leucopterin and xanthopterin, were detected in large amounts in all bright irides. The brown iris of the red-winged blackbird (Agelaius phoeniceus) by comparison contained only small amounts of these and additional unidentified compounds. The absolute and relative amounts of light-absorbing compounds in the iris varied somewhat among species of blackbirds with bright irides, and markedly within one species (brewer's blackbird, Euphagus cyanocephalus) between sexes and age classes that very in eye color. Differences in the types, numbers, and sizes of pigment organelles in the irides appeared to underlie the differences in amounts of light-absorbing compounds. Guanine was the most abundant light-absorbing compound in all bright irides, accounting for about 90% of the total absorption at 250 nm. A wide range of concentrations of guanine, from 96 to 9 micrograms per iris, produced bright irides. The primary pigment organelles of pigment cells in bright irides were reflecting platelets, which typically appeared as open spaces on electron micrographs. In the red-eyed vireo there were in addition red pterinosome-like pigment organelles in the pigment cells on the anterior surface of the iris stroma. Guanine was present even in irides with no overt reflecting platelets.

Sweetclover, Melilotus Miller, was planted in a field near Saskatoon, Saskatchewan, to determine the effects of species and cultivars on early season feeding by the sweetclover weevil, Sitona cylindricollis. The wild annual species M. infesta Guss. was consumed less than were cultivars of M. alba (Desr.), which were generally consumed less than cultivars of M. officinalis (L.). The amount of feeding injury by the weevil among nine sweetclover entries was not significantly correlated with nitrate levels in cotyledons, unifoliolate, or first trifoliolate leaves. Weevils fed equally well on entries with high and low coumarin levels. Results from greenhouse cultivar trials generally paralleled those from the field. In an experiment in which different levels of ammonium nitrate fertilizer were broadcast prior to seeding of M. officinalis cultivar Norgold, levels of nitrate ion in the foliage were significantly correlated with fertilizer regime, but not with damage indices of the weevil. These experiments suggest that the nitrate ion in isolation is not the principal factor in the deterrence to sweetclover weevil feeding in M. infesta, and that elevating nitrate levels in sweetclover leaves would not confer resistance to this insect.

SUMMARYLow quality chaffed meadow hay, containing 10·5 g N/kg dry matter (DM), was fed to four artificially reared sambar (tropical) deer (Cervus unicolor) and four red (temperate) deer (Cervus elaphus) confined indoors in metabolism crates at Palmerston North, New Zealand, during March and April 1994. Measurements were made of DM intake (DMI), apparent digestibility, nitrogen (N) retention and the time spent eating and ruminating. Voluntary food intake (VFI), measured over days 7–11, was substantially greater for red deer than for sambar deer (67 v. 36 gDM/kgW0·75/day). Dry matter intake of red deer was then restricted, so that apparent digestibility could be better compared between the two species. Eating and ruminating time/gDMI and chews during eating/gDMI were all greater for sambar deer than for red deer. Apparent digestibility of DM, organic matter (OM) and energy were low (c. 0·42) and not different between deer species. Apparent digestibility of neutral detergent fibre (NDF) and cellulose were highest for red deer, but lignin apparent digestibility was highest for sambar deer. Both deer species lost weight and were in negative N balance. However, despite their lower N intake, sambar deer lost significantly less N and liveweight per day (– 5·6 g and – 118 g) than red deer (– 12·2 g and – 258 g). It was concluded that red deer responded to a diet of low quality roughage by increasing VFI and cellulose digestion, whilst sambar deer responded with a lower VFI but greater chewing activity, improved lignin digestion and better N conservation. Rumen mean retention time should be measured in future experiments with sambar deer and red deer fed on low quality forage diets.

SUMMARYGrazing sambar and red deer in New Zealand were offered a free choice of seven different plant species (forage legumes, browse and grasses) in 1992 and 1993 and dietary preference rankings were determined. Nutritive value of plants on offer and diet selected, plant height, plant species purity and stem diameter selected (browse only) were also determined. Total nitrogen (N) and organic matter digestibility (OMD) were highest for red clover, lowest for grasses and intermediate for browse species (willow, poplar and lupin). Top dietary preference ranking was willow for sambar and red clover for red deer in both years, with Yorkshire fog and prairie grass being lowly preference ranked with both deer species. Sambar selected willow stems up to 38 mm in diameter and poplar stems up to 54 mm in diameter. When the plants were grouped into browse, grass and forage legume categories, both deer species showed a similar preference ranking for grasses. Relative to grasses, sambar showed a strong preference for browse and a low preference for forage legumes, whilst red deer showed a strong preference for forage legumes of high nutritive value and a very low preference for browse. It was calculated that sambar selected a total diet higher in condensed tannins and lignin but lower in nitrogen than that selected by red deer, with similar values for total fibre and OMD. Differences in dietary preference between the two deer species may be linked with the greater ability of sambar deer to neutralize some plant secondary compounds and their more efficient rumination pattern compared with red deer. Both sambar and red deer can be classified as intermediate feeders, having a similar preference for grasses, but differing preferences for forage legumes and browse.

SUMMARYDuring 1991/93, young sambar (5 months old) and red deer (7 months old) were confined indoors in individual pens in New Zealand and fed a pelleted concentrate diet (12 MJ ME/kgDM; 2·9% N) ad libitum for 21 months. Seasonal patterns of voluntary feed intake (VF1), liveweight gain (LWG), scrotal circumference and plasma concentrations of prolactin (PRL), luteinizing hormone (LH), testosterone (T) and progesterone (P) were compared using five stags and three hinds of each species.Red deer showed a strong pattern of seasonality, with high VFI and LWG in summer and low VF1 and LWG in winter and with peak plasma T and scrotal circumference in stags in early autumn. Compared with red deer, sambar showed weaker seasonal patterns of VFI and LWG, with maximum values in autumn and minimumvalues in spring. Over a complete 12-month cycle, sambar deer gained similar amounts of liveweight to red deer but consumed substantially less feed, thus demonstrating a more efficient conversion of feed tobodyweight. Metabolizable energy (ME) requirements for both maintenance and gain were substantially lower for sambar than for red deer. Scrotal circumference and plasma T values in sambar stags attained their highest values during late autumn, winter and spring, but with a lower magnitude than peak values for red stags. Plasma PRL concentrations were seasonal in both species, with highest values in summer and lowest values in winter. Rapid increase of plasma P was first detected in red hinds in autumn and sambar hinds in spring when they weighed 96 and 90 kg respectively, and were aged 17 and 14 months. Rapid increase of plasma T was first detected in red stags in early autumn and sambar stags in mid-autumn whenthey weighed 117 and 101 kg, and were aged 16 and 15 months respectively.It was concluded that sambar deer had endogenous cycles of VFI, body growth and hormone secretion, which were of lesser amplitude and with different seasonality from those of red deer. Young sambar deer were more efficient feed converters than red deer, and attained sexual maturity at an earlier age and lower liveweight.

Nitrate concentrations in cotyledons of 8-10-day-old field-grown seedlings of yellow sweetclover (Melilotus officinalis cv. Norgold) were determined by HPLC ion chromatography over a 3-day period. No diurnal variation in nitrate values was observed. Nitrate concentrations were also measured in cotyledons and unifoliate leaves of 18-21-day-old seedlings of Melilotus infesta Guss., an annual sweetclover resistant to sweetclover weevil feeding damage, and cv. Norgold grown in a controlled environment chamber. Nitrate levels in each species fluctuated widely but did not follow a rhythmic or diurnal pattern. There was a significant difference in nitrate levels between the species, with M. infesta having significantly higher levels both in cotyledons and in unifoliate leaves (1.65 and 1.58 mg/g, respectively) than Norgold (0.91 and 0.51 mg/g, respectively), and this interspecific difference was more consistent in the early morning.

Genome-scale scans have revealed highly heterogeneous levels of divergence between closely related taxa in many systems. Generally, a small number of regions show high differentiation, with the rest of the genome showing no or only low levels of divergence. These patterns have been interpreted as evidence for ongoing speciation-with-gene-flow, with introgression homogenizing the whole genome except loci involved in reproductive isolation. However, as the number of selected loci increases, the probability of introgression at unselected loci decreases unless there is a transmission ratio distortion causing an over-representation of specific combinations of alleles. Here we examine the transmission of three ‘speciation islands’ that contain fixed differences between the M and S forms of the mosquito,Anopheles gambiae. We made reciprocal crosses between M and S parents and genotyped over 2000 F2individuals, developing a hierarchical likelihood model to identify specific genotypes that are under- or over-represented among the recombinant offspring. Though our overall results did not match the expected number of F2genotypes, we found no biased co-transmission among M or S alleles in the three islands. Our likelihood model did identify transmission ratio distortion at two of the three islands, but this distortion was small (approx. 3%) and in opposite directions for the two islands. We discuss how our results impinge on hypotheses of current gene flow between M and S and ongoing speciation-with-gene-flow in this system.

SummaryArtificially reared sambar (tropical) deer and red (temperate) deer were confined indoors in metabolism cages and fed chaffed lucerne hay ad libitum for 4-week periods during summer and winter at Flock House Agricultural Centre, New Zealand, during 1992. Measurements were made of voluntary feed intake (VFI), apparent digestibility, faeces particle size distribution, eating and ruminating time and the rate of chewing during eating and ruminating. Red deer reduced VFI (kg DMI/day) markedly from summer to winter, associated with a reduction in the duration of each eating bout. Sambar deer slightly increased VFI over this time, associated with an increase in chewing frequency. Digestive efficiency was similar in both species, and the critical particle size for leaving the rumen was passage through a 1 mm sieve for both species. Time spent eating/g DMI was greater for sambar deer than for red deer during summer, but there was no difference during winter. Relative to red deer, sambar deer consistently spent more time ruminating/g DMI, and spent a greater proportion of total ruminating time as daytime ruminating and had more daytime ruminating bouts. Duration of each ruminating bout (min) was similar for the two deer species, but sambar deer had less chews/bolus ruminated but more rumination boli/h than red deer. Differences between sambar deer and red deer were more pronounced in ruminating than in eating behaviour, and sambar deer may have evolved a different rumination pattern to break down low-quality tropical forages more effectively.

To accelerate smolt development and downstream migration in yearling spring chinook salmon ( Oncorhynchus tshawytscha ), treatment groups at Dworshak National Fish Hatchery (Idaho) were exposed to 3-month advanced photoperiod and ambient temperature (4–6°C). In each of 3 years, photoperiod treatment began in late December or January and continued for 13 to 18 weeks until release between 29 March and 5 April into the Clearwater River. Additional groups exposed to either the advanced photoperiod or ambient light were reared at an elevated water temperature (11–12°C) for 10 to 14 days preceding release. Downstream movement and recovery proportions were evaluated using passive-integrated-transponder (PIT) tags. Photoperiod treatment increased gill Na + K + ATPase levels significantly at the time of release in 2 of the 3 study years and in all 3 years resulted in significantly faster travel times to Lower Granite Dam, 117 km downstream. The combination of photoperiod and increased temperature treatment resulted in the highest gill Na + K + ATPase levels at release, the fastest downstream movement, and significantly higher recovery proportions downstream. Temperature treatment alone had no effect on gill Na + K + ATPase level or recovery proportion and resulted in significantly slower travel time to Lower Granite Dam. Treatment groups exhibiting faster travel time to Lower Granite Dam also passed McNary Dam (343 km downstream) sooner, although the differences were not as great.

Several biological measurements were made on captive sambar deer over 3 years (1989–92). Calving occurred from January to November, with a peak in April/May. Mean calving date was 8 May (SD = 71.3 days; n = 31). Calf mortality at birth was 28% (12/43), with the major causes being adult aggression and inclement weather. Mortality was higher in stag calves (41%) than hind calves (6%). Most adult stags were in velvet antler between January and April (mean = 125 days; SD = 22.6 days), and in hard antler between May and November (mean = 231 days; SD = 40.0 days), during which time rutting behaviour was observed. Mean dates of velvet stripping and hard antler casting were 17 April (SD = 14.9 days) and 7 December (SD = 35.4 days), respectively. These data are compared with similar data for farmed red deer. Sambar deer were found to be highly nervous and temperamental, but became more settled with regular human contact and feeding with maize and hay.

SUMMARYSambar deer (n = 8) and red deer (n = 8) fawns were successfully artificially reared to 70 days of age, using ewe milk replacer, at Flock House Agricultural Centre, New Zealand, during 1991. Sambar deer fawns had a lower overall milk consumption than red deer fawns (312 v. 359 g DM/day; P < 0·05), and showed an earlier peak in milk consumption, a faster rate of decline and earlier self weaning. Birth weight as a proportion of dam liveweight was lower for sambar than for red deer, but liveweight gains to weaning (347 v. 330 g/day) and 70 day weaning weights (300 v. 30·4 kg) were similar. The age at which deer commenced a range of activities, including eating forage and ruminating, was similar for both species, except that jumping activities commenced 5 days later in sambar than in red deer (P < 0·01). Following milk feeding, sambar fawns were less active than red deer fawns. It was concluded that sambar deer fawns can be successfully artificially reared using ewe milk replacer, but that extra precautions are needed to avoid scouring and abomasal bloat, which were more prevalent in sambar than in red deer fawns.

Proanthocyanidin (PA) polymers (condensed tannins) were isolated and purified from the leaves of 26 accessions and species of sainfoin (Onobrychis). Analysis of the degradation products by HPLC revealed that epicatechin, gallocatechin and epigallocatechin were present as both terminal and extension units in all the samples studied while catechin was a terminal unit only. Quantitative analysis showed that epigallocatechin was the dominant extension unit in all of these polymers (52–63% total units). A mean degree of polymerization (DP) of 6.5 (by HPLC) and 9 (by Gel Permeation Chromatography) was obtained. The PA polymers consist principally (73–85%) of delphinidin units and 78–87% of cis-isomer units in all the samples studied.

Four colorimetric methods, vanillin-HCl, Prussian blue, 1-butanol-HCl, and H2SO4, were tested for their suitability for measurement of condensed tannins in media used for the culture of rumen bacteria. Of the four, only the H2SO4 procedure was suitable for quantifying condensed tannins in culture media at concentrations used in studies with rumen bacteria. Water reduced the extent of chromophore development in both the vanillin-HCl and 1-butanol-HCl methods. Components in the culture medium resulted in substantial color development in the absence of condensed tannins in both the vanillin-HCl and Prussian blue methods. In contrast, the H2SO4 method was not subject to a loss in chromophore yield from water or to interference from medium components. The chromophore formed was stable, and the assay enabled microgram quantities of condensed tannins to be measured in microbial medium. Condensed tannins in condensed tannin-bovine serum albumin complexes were readily quantified by the H2SO4 method. Thus, the potential exists for the H2SO4 method to quantify condensed tannins in both condensed tannin-bacterial cell and condensed tannin-bacterial enzyme complexes.

Proanthocyanidin (PA) polymers (condensed tannins) were extracted from sainfoin leaves at different stages of plant development. Analysis of the phloroglucinol degradation products by HPLC showed that catechin, epicatechin, gallocatechin, and epigallocatechin were present as terminal units at all stages, while gallocatechun and epigallocatechun were the predominant extension units with lesser amounts of epicatechin incorporated at early stages. Catechin was not incorporated as an extension unit. The number-average molecular weight and degree of polymerization increased with leaf development

Grazing behaviour was recorded in sambar deer and red deer for 24-h continuous periods, at 2-monthly intervals, over 12 months from March 1990 to March 1991. Scan-sampling was used, with observations made every 12 min. Both groups of deer grazed separate but adjoining areas of the same pasture for the duration of the study. Sambar deer grazed most actively during the night (0100–0500 h), late afternoon, and evening (1700–2100 h), whereas red deer grazed most intensely during early morning (0500–0700 h), afternoon, and early evening (1500–2000 h). This species difference in grazing pattern was not altered by season or month. Total grazing time was similar for sambar and red deer (9.1 versus 9.4 h/24 h), but sambar deer spent more time grazing during the night (6.2 versus 4.9 h/24 h; P < 0.01) and less time grazing during the day (2.9 versus 4.5 h/24 h; P < 0.01) than red deer. The ratio night grazing:daytime grazing was much greater for sambar deer (2.3:1.0) than for red deer (1.1:1.0; P < 0.001)....