Contrasted patterns of genetic differentiation across eight bird species in the Lesser Antilles

Abstract

Archipelagoes are considered as "natural laboratories" for studying processes that shape the distribution of diversity. The Lesser Antilles provide a favorable geographical context for divergence to occur. However, although morphological subspecies have been described across this archipelago in numerous avian species, the potential for the Lesser Antilles in driving intra-specific genetic divergence in highly mobile organisms such as birds remains understudied. Here, we assessed level of intra-specific genetic diversity and differentiation between three islands of the Lesser Antilles (Guadeloupe, Dominica and Martinique) using a multi-species approach on eight bird species. For each species, we built a set of microsatellite markers from cross-species amplifications. Significant patterns of inter-island and/or within-island genetic differentiation were detected in all species. However, levels of intra-specific genetic differentiation among the eight bird species were not always consistent with the boundaries of subspecies previously described in the sampled islands. These results suggest different histories of colonization/expansion and/or different species-specific ecological traits affecting gene flow, advocating for multi-species studies of historical and contemporary factors shaping the distribution of diversity on islands.

Habitat fragmentation, not habitat loss, drives the prevalence of blood parasites in a Caribbean passerine

“…Bullfinches in particular were selected for this study because they were common birds in all the studied forest fragments, from pristine to degraded ones. Although no data are available regarding its dispersal ability, previous studies revealed detectable genetic structure in this species both between islands (Khimoun et al 2016a) and within the island of Guadeloupe (Khimoun et al 2017), suggesting that the species is not very mobile.…”

“…Whereas the subspecies L. n. dominicana and L. n. noctis are described in Guadeloupe and Martinique respectively, genetic analyses do not seem to support this subspecific differentiation between islands (Khimoun et al 2016a). Although no data are available regarding its dispersal ability, previous studies revealed detectable genetic structure in this species both between islands (Khimoun et al 2016a) and within the island of Guadeloupe (Khimoun et al 2017), suggesting that the species is not very mobile. Within the species range, bullfinches inhabit all kinds of forested habitats, from continuous evergreen forest to regrown forest fragments among cultivation fields (Rising and Jaramillo 2016).…”

“…This species occurs only on the Lesser Antilles except Barbados, and several subspecies have been described based on morphological characters (Rising and Jaramillo 2016). Whereas the subspecies L. n. dominicana and L. n. noctis are described in Guadeloupe and Martinique respectively, genetic analyses do not seem to support this subspecific differentiation between islands (Khimoun et al 2016a). This bird is a primarily frugivorous species (which also consumes nectar, seeds and some animal matter) that occurs in small groups in the non-breeding season.…”

Comparative phylogeography of mainland and insular species of Neotropical molossid bats (Molossus)

“…Similarly, Muscarella, Murray, Ortt, Russell, and Fleming (), Carstens et al (), and Larsen et al () found varying population structuring in different species of phyllostomid bats in the Caribbean, ranging from some species having monophyletic populations confined to individual islands, and other species lacking any genetic structuring among islands. Similar patterns have also been observed in other groups of volant animals, such as butterflies (Davies & Bermiham., ) and birds (Khimoun et al, ).…”

Landscape genetic analyses reveal fine‐scale effects of forest fragmentation in an insular tropical bird

“…Although birds have long been regarded as less sensitive to habitat fragmentation than other taxa because of their assumed high dispersal abilities, recent works have shown that gene flow can be restricted over very short geographic distances in avian species (Arnoux et al., ; Bertrand et al., ; Khimoun, Arnoux, et al., ; Khimoun, Eraud, et al., ). In addition, a previous study based on the comparison of a continuous forest and a fragmented forest within a small island revealed that forest fragmentation affects population genetic structure in several bird species at a small spatial scale and that forest specialist species are more impacted than co‐occurring generalist species (Khimoun, Eraud, et al., ).…”