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Aim: Pleistocene climate shifts were influential in shaping biodiversity patterns for forest‐dependent species. Within southern Africa, palaeoclimatic shifts possibly homogenised subtropical Afromontane forest biodiversity, yet these forests continue to harbour unique diversity. For the three songbird species with different natural histories, we investigated the refugial role of subtropical Afromontane and scarp forests and explored specifically how palaeoclimatic events impacted genetic connectivity among forest patches. Location: Maputaland‐Pondoland‐Albany Biodiversity Hotspot, south‐eastern South Africa. Taxon: Batis capensis, Phylloscopus ruficapilla and Pogonocichla stellata. Methods: Mitochondrial control region sequences and microsatellite data were used to assess genetic diversity and population structure among 406 birds. Demographic change was inferred using Bayesian skyline plots (BSPs), and approximate Bayesian computations (ABCs) were used to identify gene flow trends among putative refugia. Environmental niche models (ENMs) were used to infer past occurrence probabilities. Results: Species BSPs supported regional presence predating the Last Glacial Maximum (21 kya) and indicated post‐glacial population expansions. ABC modelling revealed that present‐day gene flow trends emerged largely during the current interglacial (<12 kya), suggesting that thermal maxima promote regional forest expansion. The north‐eastern source of gene flow in all the three species suggested a post‐glacial influx from refugia further north, while southern scarp forests sustained secondary source populations for B. capensis and P. ruficapilla. High gene flow signatures from south‐western forests in B. capensis and especially P. stellata alluded to hidden source populations in the under‐surveyed southern Afrotemperate forests—the southernmost Afromontane forest bloc. ENMs corroborated both scarp and southern Afrotemperate forests as glacial refugia and demonstrated persistent regional population presence over the past 120 kya. Main Conclusions: The population genetics and palaeodistribution of the three bird species indicate their regional persistence throughout the late Pleistocene, suggesting that Afromontane and scarp forests of south‐eastern South Africa served as refugia for subtropical African avian forest biota. [ABSTRACT FROM AUTHOR]

Species confined to naturally fragmented habitats may exhibit intrinsic population complexity which may challenge interpretations of species response to anthropogenic landscape transformation. In South Africa, where native forests are naturally fragmented, forest‐dependent birds have undergone range declines since 1992, most notably among insectivores. These insectivores appear sensitive to the quality of natural matrix habitats, and it is unknown whether transformation of the landscape matrix has disrupted gene flow in these species. We undertook a landscape genetics study of four forest‐dependent insectivorous songbirds across southeast South Africa. Microsatellite data were used to conduct a priori optimization of landscape resistance surfaces (land cover, rivers and dams, and elevation) using cost‐distances along least‐cost pathway (LCP), and resistance distances (IBR). We detected pronounced declines in effective population sizes over the past two centuries for the endemic forest specialist Cossypha dichroa and Batis capensis, alongside recent gene flow disruption in B. capensis, C. dichroa and Pogonocichla stellata. Landscape resistance modelling showed both native forest and dense thicket configuration facilitates gene flow in P. stellata, B. capensis and C. dichroa. Facultative dispersal of P. stellata through dense thicket likely aided resilience against historic landscape transformation, whereas combined forest‐thicket degradation adversely affected the forest generalist B. capensis. By contrast, Phylloscopus ruficapilla appears least reliant upon landscape features to maintain gene flow and was least impacted by anthropogenic landscape transformation. Collectively, gene flow in all four species is improved at lower elevations, along river valleys, and riparian corridors— where native forest and dense thicket better persist. Consistent outperformance of LCP over IBR land‐cover models for P. stellata, B. capensis and C. dichroa demonstrates the benefits of wildlife corridors for South African forest‐dependent bird conservation, to ameliorate the extinction debts from past and present anthropogenic forest exploitation. [ABSTRACT FROM AUTHOR]

Aim: Forest fragmentation is a major driver of biodiversity loss causing declines in species richness and functional diversity of biotic communities. Bats are essential components of ecosystems and are useful bio‐indicators of habitat disturbance, yet the response and vulnerability of bats to fragmentation have been poorly studied in Africa. We aim to assess the effects of forest biogeographical history and fragmentation on functional diversity of bats and their functional traits. Location: Eastern Cape and southern KwaZulu‐Natal, South Africa. Taxon: Insectivorous bats. Methods: We surveyed forest‐utilizing bats to derive four functional diversity indices. Generalized linear models were used to assess the response of diversity indices to biogeographical history and fragmentation, represented by forest type and five landscape fragmentation metrics. RLQ and fourth‐corner analysis were used to investigate the interaction of traits with fragmentation metrics and forest type. Results: Pondoland Scarp forests displayed high functional richness, while Eastern Cape Dune forests exhibited high functional divergence yet low functional richness and dispersion. Two fragmentation metrics affected functional diversity dynamically: edge density had a positive effect on functional evenness; and dispersion was negatively affected by river length through forests. Results showed stronger interactions of functional traits with forest type than fragmentation metrics, with filtering effects on body size and wing morphology. Main conclusions: The large‐scale processes related to biogeographical history, and associated forest structure, are important determinants of functional richness, divergence and dispersion of insectivorous bat communities. Scarp forests showed the highest species and functional richness as they experienced less extreme climatic extinction filtering than Mistbelt forests during the Last Glacial Maximum, whereas the low diversity of Eastern Cape Dune forests results from their younger evolutionary history and homogenous vegetation structure. Little is known of the sensitivity of bats to habitat fragmentation in Africa: here, we show larger‐sized insectivorous species; and species exhibiting low wing loading may be more vulnerable to fragmentation. [ABSTRACT FROM AUTHOR]

Individual specificity can be found in the vocalizations of many avian and mammalian species. However, it is often difficult to determine whether these vocal cues to identity rise from 'unselected' individual differences in vocal morphology or whether they have been accentuated by selection for the purposes of advertising caller identity. By comparing the level of acoustic individuality of different vocalizations within the repertoire of a single species, it is possible to ascertain whether selection for individual recognition has modified the vocal cues to identity in particular contexts. We used discriminant function analyses to determine the level of accuracy with which calls could be classified to the correct individual caller, for three dwarf mongoose ( Helogale parvula) vocalizations: contact, snake, and isolation calls. These calls were similar in acoustic structure but divergent in context and function. We found that all three call types showed individual specificity but levels varied with call type (increasing from snake to contact to isolation call). The individual distinctiveness of each call type appeared to be directly related to the degree of benefit that signalers were likely to accrue from advertising their identity within that call context. We conclude that dwarf mongoose signalers have undergone selection to facilitate vocal individual recognition, particularly in relation to the species' isolation call. [ABSTRACT FROM AUTHOR]

Many mammal species adopt marking postures that elevate their scent deposits. The most extreme of these is handstand marking, in which an individual reverses against an upright object, flings its hind legs into the air above its back and balances bipedally on its fore feet. The resulting anogenital deposit is thus raised one full body length above ground level. It has been suggested that this energetically costly form of marking serves to provide conspecifics with information about the marker's body size and hence competitive ability. However, this explanation assumes that the height of an individuals' deposit does reflect accurately its body size, an assumption that has never been tested in any hand-standing species. This study investigated the relationship between body size and handstand mark height in a wild population of dwarf mongooses ( H elogale parvula) in South Africa. We found that although body size and marking height were correlated positively for female dwarf mongooses, they were not related for males. Male dwarf mongooses (who are subject to intrasexual competition from outside their group) invested more heavily in anogenital range marking, marking at three times the female frequency and placing their deposits significantly higher than females (although they were not dimorphic). Males that were particularly vulnerable to rivals (i.e. those that were small for their age) tended to mark higher than more robust age-mates, in keeping with the predictions of Adams & Mesterton-Gibbons' (1995, J. Theor. Biol.175, 405-421). model of deceptive threat communication. These findings suggest strongly that the height of anogenital scent deposits is of social significance to dwarf mongooses. [ABSTRACT FROM AUTHOR]

The red-chested cuckoo Cuculus solitarius parasitises many passerines in Africa, but some common species sympatric with this brood parasite are rarely used as hosts. We tested the responses of three turdid hosts to parasitism with artificial cuckoo eggs. The kurrichane thrush Turdus libonyana, which is not regularly parasitized by the cuckoo, rejected 60% of mimetic model eggs and 81% of non-mimetic eggs. We observed female thrush behaviour during the first visit after parasitism, and thrushes appeared to be initially fooled by mimetic eggs in completed clutches in all cases, and incubated. By contrast, in half of the experiments with non-mimetic eggs, these were ejected by the thrushes, with the host grasping the egg and flying away with it. The time spent nest checking prior to ejection was only one third of the time spent nest checking when females decided to incubate the clutch, suggesting that females were immediately aware of a foreign egg in the nest. By contrast, southern olive thrushes T. olivaceous rejected all non-mimetic and accepted all mimetic model eggs, whereas cape robins Cossypha caffra accepted all model eggs, irrespective of whether or not they were mimetic. Our results support the hypothesis that rejection behaviour in these two thrush species evolved as a defence against interspecific nest parasitism, with thrushes appearing to be ahead in this particular host-parasite arms race. The cape robin, by contrast, appears not to reject cuckoo eggs, either because it is to unable to recognize them, or because the costs associated with removal may be too high. [ABSTRACT FROM AUTHOR]

Abstract In the continuing arms race between hosts and brood parasites, hosts are expected to reduce variation in the appearance of their own eggs within clutches, as it facilitates recognition of parasitic eggs. At the same time, by increasing interclutch variation, hosts should make it more difficult for parasites to evolve perfectly mimetic eggs. In this study, we experimentally manipulated intraclutch variation in the great reed warbler, Acrocephalus arundinaceus , in Hungary, where this species is heavily (c . 64%) parasitized by the common cuckoo, Cuculus canorus . We placed artificial cuckoo eggs, which appeared moderately mimetic to humans, in two groups of nests; in one group we increased variability of egg appearance within clutches by exchanging host eggs among nests. These clutches showed a significantly higher intraclutch variability than natural clutches, which we used as a control group. Our results indicate that it has no effect on rejection behaviour in this species, neither when variation was increased experimentally, nor within the natural range of variation displayed by our population. We suggest that when parasitism is high, selection for reduced intraclutch variation may be less important than frequency-dependent selection for increased variation between individuals within a host population. [ABSTRACT FROM AUTHOR]

The Violet Woodhoopoe Phoeniculus damarensis damarensis is considered a threatened subspecies and one of ten bird taxa endemic to Namibia and southwestern Angola. This species is distinguished from the more common and widespread Green Woodhoopoe P. purpureus by a variable plumage trait, resulting in uncertainty as to the distribution and degree of overlap between these taxa. Mitochondrial sequences from the cytochrome oxidase I (COI) gene show minimal divergence among Namibian woodhoopoes (0.15%, including P. d. damarensis and P. p. angolensis), and low divergence between Namibian birds and South African (1.06%, P. p. purpureus) or Kenyan (2.30%, P. p. marwitzi) Green Woodhoopoes. Sequences from Namibian woodhoopoes are phylogenetically nested within P. purpureus, rendering this species paraphyletic at mitochondrial DNA. Genetic divergences among Violet and Green Woodhoopoes fall within the range of intraspecific values recorded for avian mitochondrial protein coding genes, and are substantially less than most interspecific values. Comparisons with the related Scimitarbill Rhinopomastus cyanomelas suggest that the low divergences among Green and Violet Woodhoopoes are not an artefact of slow evolutionary rates in Phoeniculidae. We suggest that in the absence of evidence for evolutionary independence or a clear phenotypic diagnosis, the Violet Woodhoopoe should be synonymized with the Green Woodhoopoe. It is the status of this taxon that should be considered in formulating priorities for avian conservation in Namibia. [ABSTRACT FROM AUTHOR]

This article presents a response by the author to an article written by Simmon et al. The author and his team conducted a preliminary mitochondrial DNA sequence study of woodhoopoes with the aim of acquiring diagnostic molecular markers to study interbreeding between two poorly differentiated forms. This study has revealed a surprisingly close relationship between 12 violetmantled birds from two localities in northwestern Namibia and green-mantled birds several thousand kilometres away in South Africa and Kenya; it was also found negligible differentiation between these violet-mantled birds and a single green-mantled bird from a mixed flock in Namibia.