Biologia Futura: rapid diversification and behavioural adaptation of birds in response to Oligocene–Miocene climatic conditions

Abstract

Our knowledge about the origin of landbirds (Telluraves) is increasing rapidly but new questions are arising because of the contradictory findings from previous studies. All of the major lineages in the highly diverse clade of Neoaves have a Gondwanan origin, although studies often disagree about the origin of different sub-lineages. Nevertheless, understanding the biogeographical histories of these groups (e.g. Accipitriformes, Passeriformes) is important when studying the evolution of variation in life history and behavioural traits. Therefore, we would like to find answers to questions such as which biogeographic changes affected the radiation of birds? When did the most influential climatic events affect the diversification of birds? What behavioural adaptations occurred in response to those large-scale changes? The major orogenetic events in Asia and South America formed specific corridors that enabled the radiation of birds. The climatic changes and habitat differentiation they caused during the Oligocene-Miocene era made the divergence of birds possible through their adaptation to newly available niches. Consequently, variation in life history and behavioural traits emerged as adaptive outcomes of changes in foraging, nestling and migratory behaviours.

Evolution of Songbirds (Passeriformes) and their Presence in the Neogene and the Quaternary in the Carpathian Basin

“…The earliest known Palaearctic remains come from the Upper Oligocene (MP 30) from sites at Coderet and Gannat (Allier) in France (Mourer-Chauviré et al 1989). Typically, these finds already bear the osteomorphological signs indicating passerines (Nagy 2020). Thereafter, fossils from Europe, Asia, and also from North and South America are only known from the Lower Miocene.…”

The evolution of egg colour and patterning in Australian songbirds

“…The passerine clade (Passeriformes) comprises over half of all extant birds worldwide. The Gondwanan radiation of passerines firmly roots the origin of oscines in modern-day Australasia (Barker et al 2004;Nagy 2020), and the Australian avifauna still contains many endemic and phylogenetically distinct lineages that represent the earliest parts of the passerine radiation. Passeriformes subsequently further diversified when orders and families radiated out of Australasia, into Eurasia, Africa and the new world, as early as 55 million years ago (Barker et al 2004;Oliveros et al 2019;Nagy 2020).…”

“…brood parasites, partners or predators, or it may act as a protective layer for the embryo to prevent damaging solar radiation, water loss, and bacterial infections (Moreno and Osorno 2003;Kilner 2006;Cherry and Gosler 2010;Maurer et al 2011). Recent studies have suggested that egg colour may have thermoregulatory benefits (Wisocki et al 2020), and that egg pigmentation may be associated with the variation in nest type across species (Nagy et al 2019). Nest types can have a large impact on embryo survival, whereby well-structured nests (e.g., with a roof) will provide greater protection, warmth, and camouflage than exposed nests (e.g., open cups).…”

“…Nest types can have a large impact on embryo survival, whereby well-structured nests (e.g., with a roof) will provide greater protection, warmth, and camouflage than exposed nests (e.g., open cups). However, these recent studies (Nagy et al 2019;Wisocki et al 2020) have taken a global perspective which, due to the vast variability in climate and the uneven phylogenetic structuring across continents, may obscure evolutionary transitions over time (Cockburn and Russell 2011).…”

“…Although egg colour can be a somewhat labile trait across avian families (Cassey et al 2010), there is a strong phylogenetic signal in both egg colouration (Cassey et al 2012) and nest type (Price and Griffith 2017). Furthermore, although the recent study by Nagy et al (2019) covers 855 species across 90 families, and provides an excellent global overview of the contemporary covariation between egg colour and nest type in the birds broadly, it suffers from incomplete sampling across the phylogeny and is limited in separating out endemic and nonendemic species distributions. Additional insight can, therefore, be gained through a more comprehensive examination of a single clade in its endemic region.…”