11 results on '"LAURENTIAN"'
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2. Laser-ablation Lu-Hf dating reveals Laurentian garnet in subducted rocks from southern Australia
- Author
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Dillon A. Brown, Alexander Simpson, Martin Hand, Laura J. Morrissey, Sarah Gilbert, Renée Tamblyn, Stijn Glorie, Brown, Dillon A, Simpson, Alexander, Hand, Martin, Morrissey, Laura J, Gilbert, Sarah, Tamblyn, Renee, and Glorie, Stijn
- Subjects
Laurentian ,Laser-ablation ,laser ablation ,Australia ,garnet ,metapelitic rocks ,Geology - Abstract
Garnet is a fundamental expression of metamorphism and one of the most important minerals used to constrain the thermal conditions of the crust. We used innovative in situ laser-ablation ICP-MS/MS Lu-Hf geochronology to demonstrate that garnet in metapelitic rocks enclosing Cambrian eclogite in southern Australia formed during Laurentian Mesoproterozoic metamorphism. Garnet porphyroblasts in amphibolite-facies metapelitic rocks yielded Lu-Hf ages between 1286 ± 58 Ma and 1241 ± 16 Ma, revealing a record of older metamorphism that was partially obscured by metamorphic overprinting during ca. 510 Ma Cambrian subduction along the East Gondwana margin. Existing detrital zircon age data indicate the protoliths to the southern Australian metapelitic rocks were sourced from western Laurentia. We propose that the metapelitic rocks of southern Australia represent a fragment of western Laurentian crust, which was separated from Laurentia in the Neoproterozoic and incorporated into the East Gondwana subduction system during the Cambrian. The ability to obtain Lu-Hf isotopic data from garnet at acquisition rates comparable to those for U-Pb analysis of detrital zircon means, for the first time, the metamorphic parentage of rocks as expressed by garnet can be efficiently accessed to assist paleogeographic reconstructions.
- Published
- 2022
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3. Repurposing of archived CO1 sequence data reveals unusually high genetic structure between North American and European zebra mussels (Dreissena polymorpha)
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Andrew A. David and Kendall Gardner
- Subjects
dreissena polymorpha ,laurentian ,big data ,invasion ,Genetics ,QH426-470 - Abstract
The invasion of the zebra mussel, Dreissena polymorpha in the Great Lakes of North America is regarded as one of the most catastrophic ecological events in recent history. Previous studies showed a close kinship between European zebra mussels and their invasive cohorts in the Great Lakes. In this study, we repurposed and reanalyzed archived CO1 sequence data from Lake Superior and multiple sites in Europe that were collected between 1991 and 2011 to illustrate an interesting pattern of genetic isolation that was overlooked in previous studies. The results showed extreme genetic isolation of Lake Superior zebra mussels as evident by high ϕST values and strong geographic patterning of Lake Superior haplotypes.
- Published
- 2017
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4. Repurposing of archived CO1 sequence data reveals unusually high genetic structure between North American and European zebra mussels ( Dreissena polymorpha ).
- Author
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David, Andrew A. and Gardner, Kendall
- Subjects
ZEBRA mussel ,DREISSENA ,HAPLOTYPES ,ECOLOGY - Abstract
The invasion of the zebra mussel, Dreissena polymorpha in the Great Lakes of North America is regarded as one of the most catastrophic ecological events in recent history. Previous studies showed a close kinship between European zebra mussels and their invasive cohorts in the Great Lakes. In this study, we repurposed and reanalyzed archived CO1 sequence data from Lake Superior and multiple sites in Europe that were collected between 1991 and 2011 to illustrate an interesting pattern of genetic isolation that was overlooked in previous studies. The results showed extreme genetic isolation of Lake Superior zebra mussels as evident by high ϕ
ST values and strong geographic patterning of Lake Superior haplotypes. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
5. Late Proterozoic reconstructions of North-West Scotland and Central Canada: Magnetic fabrics, paleomagnetism and tectonics
- Author
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Borradaile, Graham J. and Geneviciene, Ieva
- Subjects
- *
PROTEROZOIC stratigraphic geology , *PALEOMAGNETISM , *STRUCTURAL geology , *ANISOTROPY - Abstract
Abstract: Red-beds dominate the Stoer Group and the unconformably overlying Torridon Group, having accumulated between ∼1400 and ∼1000Ma, in a rift of the Hebridean foreland. The sequences were weakly strained and shortened E–W, and each underwent successive diagenetic changes which altered their magnetic properties and caused their different characteristic post-depositional magnetizations. Anisotropy of magnetic susceptibility (AMS) reveals an N–S vertical tectonic foliation superimposed on the bedding-planar AMS sub-fabric. The tectonic AMS sub-fabric was isolated by comparing normalized and non-normalized mean tensors of multiple specimens. The N–S vertical AMS tectonic foliation postdates warps of bedding; thus the high-susceptibility minerals, including those carrying palaeomagnetic signals re-oriented or recrystallized after deposition and diagenesis. Thus characteristic remanence vectors (ChRM) were acquired long after deposition, first in the Stoer Group, then in the Torridon. ChRMs were isolated for 143 Stoer specimens and 94 Torridon specimens using two cycles of low-temperature demagnetization followed by at least 12 steps of thermal demagnetization. For the Stoer Group, two structurally integral groups of sites yield mean magnetizations of 317.0/+43.1 α 95 =11.3 (n =49) and 309.9/52.1 α 95 =10.6 (n =23). Some Stoer specimens bear a Torridon age overprint 133.3/+525 α 95 =9.6 (n =19). The younger Torridon Group yields 138.4/+52.2 α 95 =7.4 (n =42); 134.9/+45.5 α 95 =16.0 (n =15) and 134.4/+55.1 α 95 =11.3 (n =19) from three structurally integral clusters of sites. These late chemical magnetizations postdate bedding warps, faults and tectonic AMS fabrics; they do not warrant local “rigid-body” tilt corrections. However, we restored the ChRM directions for the regional post-Cambrian eastwards tilt which affected the entire foreland from the Lewisian basement to the overlying Proterozoic strata. Paleopoles calculated from the strata''s restored vectors were rotated into Laurentian coordinates for comparison with Canadian Proterozoic palaeopoles. The Stoer Group was magnetized in a normal polarity geomagnetic field whereas the Torridon Group was magnetized in a reversed polarity epoch. However, both sequences include at least one polarity transition, indicating long duration chemical magnetizations successfully averaging secular variation. At a minimum, red-bed magnetization processes exceeded 0.1Ma and may have encompassed several million years. During Stoer Group magnetization, the Hebridean craton was at paleolatitudes of 26–44°N; when the Torridon Group magnetized it was at 23–27°S. Accepting published ages, this defines a minimum southward latitudinal displacement rate of 27–40km/Ma. Restored Stoer Group paleopoles lie in the present-day north-central Pacific Ocean (∼190E/25N); corresponding to the Laurentian APWP dated at between 1090 and 1109Ma. Torridon Group paleopoles lie in the south-central Pacific (∼210E/25S) near the poorly documented (<900Ma) southernmost part of the Laurentian APWP. [Copyright &y& Elsevier]
- Published
- 2008
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6. Comment on Alley et al. (2006): “Outburst flooding and the initiation of ice-stream surges in response to climatic cooling: A hypothesis”, Geomorphology 75, 76–89
- Author
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Erlingsson, U.
- Subjects
- *
AUFEIS , *ICE streams , *CLIMATE change , *PHYSICAL geography - Abstract
Abstract: While the paper by Alley et al. (Alley, R.B., Dupont, T.K., Parizek, B.R., Anandakrishnan, S., Lawson, D.E., Larson, G.J., Evenson, E.B., 2006. Outburst flooding and the initiation of ice-stream surges in response to climatic cooling: A hypothesis. Geomorphology 75, 76–89) is a welcome contribution as it presents some new arguments and expands the discussion, it unfortunately overlooked the literature on the captured ice shelf (CIS) hypothesis. Considering all recent results, the hypothesis has the potential for drastically altering our understanding of sudden climate change during the Quaternary period. Also, the interpretation of macrogeomorphology in land-ice covered continents and seas, including the Hudson Bay and the Baltic Sea, is affected. [Copyright &y& Elsevier]
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- 2007
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7. Buried Dreams: Refitting and Ritual at the Mount Albert Site, Southern Ontario
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Forsythe, Kyle D
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ceremonial practices ,bannerstones ,Middle Archaic ,Laurentian ,Brewerton ,refitting ,experimental archaeology ,lithic analysis ,ritual breakage ,Archaeological Anthropology - Abstract
Few intact Middle Archaic sites have been investigated in Southwestern Ontario and attention has focused on large, multicomponent sites, which are difficult to interpret. This thesis focuses on recent work that has been conducted on an undisturbed, single-component Brewerton site in Mount Albert south of Lake Simcoe, where the lithic assemblage presents an unprecedented view of lifeways in the Middle Archaic (ca. 5000-4500 B.P.). Notable is the presence of high numbers of fragmented formal flaked stone tools - moreso than is consistent with solely tool production activities. The thesis evaluates the possibility that the artifacts were intentionally destroyed as part of previously undocumented ceremonial practices in the region. Refitting of the pieces and experimental breakage of reproduction bifaces each offer insights into strategies for the purposeful breakage of stone artifacts.
- Published
- 2016
8. Investigating invasive population genetics of rainbow smelt (Osmerus mordax) in the Laurentian Great Lakes Region
- Author
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Dobosenski, Jamie
- Subjects
- Fisheries, Genetics, Invasives, Laurentian, Populations, Smelt
- Abstract
Increasing our understanding of aquatic invasive species is important because of the negative influence they can have on the economies and ecosystems of invaded regions by negatively affecting ecotourism as well as commercial and recreational fisheries. There is growing interest in how environmental variability (e.g. temperature) and stochastic invasion events (e.g. founder effect) affect the genetic composition of populations of invasive species. Rainbow smelt (Osmerus mordax) are a cold-water, planktivorous fish that spread into the Great Lakes basin in the early 1900s. We performed genetic analyses using microsatellites to determine if a temperature induced mortality event affected the genetic structure of a population of invasive rainbow smelt and to also investigate the influence stochastic invasion events have had on the genetic composition of invasive rainbow smelt populations across broad geographic ranges. Overall, there was no genetic difference in rainbow smelt collected before, during, or after the temperature induced mortality event. To investigate the influence stochastic invasion events have on populations of invasive rainbow smelt, we conducted population genetics analyses on rainbow smelt specimens from Lake Ontario, Lake Michigan, Lake Superior, and four inland lakes in Northern Wisconsin. Most population pairs had pairwise Fst values significantly different than zero except two comparisons. Based on clustering analysis and PCoA analysis, four distinct population clusters were identified. Overall, this study provides evidence that founder effects have more of an impact on invasive rainbow smelt population diversity than extreme population reductions.
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- 2018
9. Hypoxia In The Lower St. Lawrence Estuary: How Physics Controls Spatial Patterns
- Author
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Lefort, S., Gratton, Y., Mucci, A., Dadou, I., Gilbert, D., GEOTOP and Department of Earth and Planetary Sciences, McGill University = Université McGill [Montréal, Canada], Centre Eau Terre Environnement [Québec] (INRS - ETE), Institut National de la Recherche Scientifique [Québec] (INRS), DYNBIO LEGOS, Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Fisheries and Oceans Canada, Maurice Lamontagne Institute, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,ORGANIC-MATTER ,UPWELLING SYSTEM ,GULF ,RESPIRATORY ACTIVITY ,BOTTOM WATERS ,GEOCHEMICAL EVIDENCE ,TROUGH ,LAURENTIAN ,COASTAL OCEAN ,CARBON BUDGET ,OXYGEN - Abstract
ISI Document Delivery No.: 980RD Times Cited: 1 Cited Reference Count: 57 Cited References: Anschutz P, 2000, GEOCHIM COSMOCHIM AC, V64, P2751, DOI 10.1016/S0016-7037(00)00400-2 Benoit P, 2006, MAR CHEM, V102, P13, DOI 10.1016/j.marchem.2005.09.015 Bograd SJ, 2008, GEOPHYS RES LETT, V35, DOI 10.1029/2008GL034185 Bugden G.L., 1991, CANADIAN SPECIAL PUB, V113, P139 CHAPMAN DC, 1985, J PHYS OCEANOGR, V15, P1060, DOI 10.1175/1520-0485(1985)0152.0.CO;2 Cloern JE, 2001, MAR ECOL PROG SER, V210, P223, DOI 10.3354/meps210223 Colombo JC, 1996, MAR CHEM, V51, P277, DOI 10.1016/0304-4203(95)00059-3 Colombo JC, 1996, MAR CHEM, V51, P295, DOI 10.1016/0304-4203(95)00060-7 Craig J, 2008, AZMP B PMZA, V7, P37 Czeschel R, 2011, J GEOPHYS RES-OCEANS, V116, DOI 10.1029/2010JC006565 Diaz R. J., 2009, HYPOXIA, P1, DOI 10.1016/S1546-5098(08)00001-0 Diaz RJ, 2001, J ENVIRON QUAL, V30, P275 Dickie L.M., 1983, ESTUARIES ENCLOSED S, P403 Galbraith PS, 2006, J GEOPHYS RES-OCEANS, V111, DOI 10.1029/2005JC003159 Genovesi L, 2011, LIMNOL OCEANOGR, V56, P1319, DOI 10.4319/lo.2011.56.4.1319 Gilbert D, 2005, LIMNOL OCEANOGR, V50, P1654 Gilbert D., 2004, ICES ANN SCI C INT C Gilbert D, 2010, BIOGEOSCIENCES, V7, P2283, DOI 10.5194/bg-7-2283-2010 Gilbert D, 1997, CAN J FISH AQUAT SCI, V54, P57, DOI 10.1139/cjfas-54-S1-57 GLUD RN, 1994, DEEP-SEA RES PT I, V41, P1767 Grasshoff K, 1999, METHODS SEAWATER ANA, DOI DOI 10.1002/9783527613984 GRATTON Y, 1988, J GEOPHYS RES-OCEANS, V93, P6947, DOI 10.1029/JC093iC06p06947 Gutknecht E., 2011, BIOGEOSCI DISCUSS, V8, P3537, DOI DOI 10.5194/BGD-8-3537-2011 Han GQ, 1999, J PHYS OCEANOGR, V29, P1279, DOI 10.1175/1520-0485(1999)0292.0.CO;2 Johnson C., 1987, NUMERICAL SOLUTION P Katsev S, 2007, LIMNOL OCEANOGR, V52, P2555, DOI 10.4319/lo.2007.52.6.2555 Koutitonsky V. G., 1991, CAN SPEC PUBL FISH A, V113, P139 LARGE WG, 1994, REV GEOPHYS, V32, P363, DOI 10.1029/94RG01872 LeBlond P. H., 1978, WAVES OCEAN LEDWELL JR, 1993, NATURE, V364, P701, DOI 10.1038/364701a0 Lehmann MF, 2009, LIMNOL OCEANOGR, V54, P2157, DOI 10.4319/lo.2009.54.6.2157 LUCOTTE M, 1991, ESTUAR COAST SHELF S, V32, P297, DOI 10.1016/0272-7714(91)90022-4 Matear RJ, 2003, GLOBAL BIOGEOCHEM CY, V17, DOI 10.1029/2002GB001997 Mathworks Inc, 2006, PART DIFF EQ TOOLB U Mohrholz V, 2008, CONT SHELF RES, V28, P424, DOI 10.1016/j.csr.2007.10.001 Monteiro PMS, 2011, ENVIRON RES LETT, V6, DOI 10.1088/1748-9326/6/2/025002 Monteiro PMS, 2008, DEEP-SEA RES PT I, V55, P435, DOI 10.1016/j.dsr.2007.12.010 Monteiro PMS, 2006, GEOPHYS RES LETT, V33, DOI 10.1029/2006GL026234, Monteiro PMS, 1999, ESTUAR COAST SHELF S, V49, P877, DOI 10.1006/ecss.1999.0550 Muzuka ANN, 1999, MAR GEOL, V160, P251, DOI 10.1016/S0025-3227(99)00022-5 Ozsoy E, 1997, EARTH-SCI REV, V42, P231, DOI 10.1016/S0012-8252(97)81859-4 Packard T.T., 1985, Advances in Aquatic Microbiology, V3, P207 Pena MA, 2010, BIOGEOSCIENCES, V7, P933 Saucier FJ, 2003, J GEOPHYS RES-OCEANS, V108, DOI 10.1029/2000JC000686 SAVENKOFF C, 1995, CONT SHELF RES, V15, P613, DOI 10.1016/0278-4343(94)00041-K Savenkoff C, 2001, ESTUAR COAST SHELF S, V52, P565, DOI 10.1006/ecss.2001.0774 Savenkoff C, 1996, CAN J FISH AQUAT SCI, V53, P2451, DOI 10.1139/cjfas-53-11-2451 Sherwood OA, 2011, P NATL ACAD SCI USA, V108, P1011, DOI 10.1073/pnas.1004904108 Silverberg N, 2000, DEEP-SEA RES PT II, V47, P699, DOI 10.1016/S0967-0645(99)00123-X Smith GC, 2006, J PHYS OCEANOGR, V36, P1485, DOI 10.1175/JPO2927.1 Smith JN, 1999, LIMNOL OCEANOGR, V44, P207 Taylor KE, 2001, J GEOPHYS RES-ATMOS, V106, P7183, DOI 10.1029/2000JD900719 TEE KT, 1989, J GEOPHYS RES-OCEANS, V94, P8075, DOI 10.1029/JC094iC06p08075 Thibodeau B, 2010, GEOPHYS RES LETT, V37, DOI 10.1029/2010GL044771 Thibodeau B, 2006, MAR GEOL, V231, P37, DOI 10.1016/j.margeo.2006.05.010 VOSJAN JH, 1987, LIMNOL OCEANOGR, V32, P767 VOSJAN JH, 1990, NETH J SEA RES, V25, P89, DOI 10.1016/0077-7579(90)90011-5 Lefort, S. Gratton, Y. Mucci, A. Dadou, I. Gilbert, D. Gilbert, Denis/A-3067-2010 Gilbert, Denis/0000-0002-9554-9594 NSERC Strategic grant; DFO CCSI (Climate Change Science Initiative) grant; Department of Earth and Planetary Sciences/McGill; GEOTOP-UQAM-McGill research center; LEGOS laboratory; University of Toulouse III (Paul Sabatier, France) This research was funded by a NSERC Strategic grant to A.M., D.G. and Y.G, and a DFO CCSI (Climate Change Science Initiative) grant to D.G. Additional financial support to S.L. was provided by the Department of Earth and Planetary Sciences/McGill, the GEOTOP-UQAM-McGill research center, the LEGOS laboratory and the University of Toulouse III (Paul Sabatier, France). We thank the captains and crew of R/V Alcide C. Horth and R/V Coriolis II for their help during the numerous cruises between 2002 and 2011. We acknowledge the two anonymous reviewers for their insightful comments. 1 AMER GEOPHYSICAL UNION WASHINGTON J GEOPHYS RES-OCEANS; A laterally integrated advection-diffusion two-dimensional model was implemented to simulate the spatial distribution of dissolved oxygen and the development of hypoxic conditions in the deep waters of the Laurentian Channel (Estuary and Gulf of St. Lawrence, Eastern Canada). Our simulations reveal that the horizontal distribution of dissolved oxygen in the bottom waters of the Laurentian Channel is determined by a combination of physical and biogeochemical processes, whereas its vertical distribution is governed by the deep water circulation. This result strongly suggests that the physics of the system and the source water properties are mostly responsible for the generation of a mid-water column oxygen minimum and the oxygen distribution pattern in the deep water column.
- Published
- 2012
- Full Text
- View/download PDF
10. Intralacustrine speciation of Salvelinus namaycush in Lake Superior: An investigation of genetic and morphological variation and evolution of lake trout in the Laurentian Great Lakes.
- Author
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Curtis, Mary Kathryn Burnham
- Subjects
- Evolution, Genetic Variation, Great, Intralacustrine, Investigation, Lake, Lakes, Laurentian, Morphological, Namaycush, Salvelinus, Speciati, Speciation, Superior, Trout
- Abstract
Hypotheses of intralacustrine speciation are tested for phenotypically divergent populations of lake trout (Salvelinus namaycush) with molecular genetic, morphometric, and osteological investigations. Three recognizable forms of Salvelinus namaycush inhabit Lake Superior. The different phenotypes are recognized based on facial and skull characteristics, fat content, and temporal and spatial reproductive characteristics. The lean inhabits inshore areas less than 70 meters deep, the siscowet inhabits waters deeper than 80 meters, and the humper lives over isolated shoals surrounded by water greater than 100 meters. Lean lake trout are found in virtually every deep lake in northern North America, in contrast to the siscowet and humper that are endemic to Lake Superior. Differences were thought to be ecophenotypic but controlled hatchery experiments demonstrated a genetic component. Differences in the morphology of the opercle and supraethmoid bones between siscowet-humper and lean phenotypes are 90% consistent and provide additional support for a genetic component to phenotypic differentiation. I used mitochondrial DNA restriction fragment length polymorphisms and morphometric measurements employing principal components to analyze the relative contributions of environment and genotype to phenotypic divergence. Biochemical genetic analysis of mitochondrial DNA indicates the presence of a hypervariable genome. No differences among the mtDNA genotypes justify species level discrimination among lean, siscowet, and humper phenotypes. Levels of sequence divergence ranged from 0.01% to 1.7% between phenotypes, comparable to within-species levels of divergence for other salmonids. Widely shared mtDNA clonal haplotypes suggest that there has been gene flow among the three forms in Lake Superior. The failure of morphometrics of wild leans and siscowets to corroborate the discrimination observed in the hatchery puts in question the breadth of the genetic basis for the morphometric characters of wild lake trout. The humper phenotype showed a mosaic of molecular-genetic, morphological, osteological, and life history differences that support a hypothesis of hybrid origin in post-glacial Lake Superior. Subtle genetic differences are probably limited to regulatory or modifier genes in the nuclear genome that govern metabolism and growth. Divergence in ecological adaptations with partial reproductive isolation by differences in time and place of spawning is suggested as the probable precedent to intralacustrine speciation.
- Published
- 1993
11. 093-04: Canadian Pacific Railway Train
- Author
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Sternberg, George Fryer, 1883-1969, Sternberg, George Fryer, 1883-1969, Sternberg, George Fryer, 1883-1969, and Sternberg, George Fryer, 1883-1969
- Abstract
This black and white photograph features the Canadian Pacific Railway train making its way up the Laurentian Mountains in Quebec, Canada. The train is crossing a dirt road on the railroad tracks. A corral is in the foreground. A small building and trees are seen in the background.
- Published
- 1912
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