Biogeography in deep time – What do phylogenetics, geology, and paleoclimate tell us about early platyrrhine evolution?

Abstract

a b s t r a c tMolecular data have converged on a consensus about the genus-level phylogeny of extant platyrrhine monkeys, but for most extinct taxa and certainly for those older than the Pleistocene we must rely upon morphological evidence from fossils. This raises the question as to how well anatomical data mirror molecular phylogenies and how best to deal with discrepancies between the molecular and morphological data as we seek to extend our phylogenies to the placement of fossil taxa.Here I present parsimony-based phylogenetic analyses of extant and fossil platyrrhines based on an anatomical dataset of 399 dental characters and osteological features of the cranium and postcranium.

Oldest known cranium of a juvenile New World monkey (Early Miocene, Patagonia, Argentina): Implications for the taxonomy and the molar eruption pattern of early platyrrhines

“…Only an exhaustive phylogenetic analysis of Oligocene to recent platyrrhines can establish the most parsimonious arrangement of the fossil taxa in relation to the living radiations of Platyrrhini. Such an analysis has been undertaken recently and it strongly supports the view that Homunculus and other Early Miocene platyrrhines are stem forms not specially related to any of the three living families (Kay, 2014; see also Kay, Fleagle and colleagues;Kay et al, 2008;Kay and Fleagle, 2010). MPM-PV 3505 provides the first information about the dental eruption sequence in an Early Miocene platyrrhine.…”

Pliocene Primates

“…Such sampling bias undoubtedly influences our knowledge of the Pliocene Neotropical primate fossil record, as monkeys were probably confined to more tropical, lower lying regions. Fossil and molecular evidence indicate that the three major clades of modern platyrrhines were established in the Miocene (Kay 2015), but as in other groups of primates, further divergence subsequently occurred. In titi monkeys, for example, the Pliocene saw the split between the donacophilus and moloch groups (Byrne et al 2016).…”

“…In titi monkeys, for example, the Pliocene saw the split between the donacophilus and moloch groups (Byrne et al 2016). The Pliocene also witnessed an important dispersal of monkeys northwards into Central America, made possible by the connection through the Isthmus of Panama between the continents of South and North America around 3.5 Ma (Kay 2015). There are currently no fossil data reflecting this dispersal, inferred from molecular data (Kay 2015), and which is part of a much bigger movement of mammals, the Great American Interchange, that occurred when the continents joined in the Pliocene.…”

Paleoenvironmental and Sea‐Level Change

“…The isolation of South America from North America (which occurred around 90 -100 Ma) ended in the Pliocene. Although fossil evidence indicates that monkeys crossed a narrow seaway between the two continents in the early Miocene (Bloch et al 2016), by at least 3.5 Ma the Isthmus of Panama (a physical land connection created either by tectonic activity or lowering of sea levels), allowed greater movement of primates into what is now Central America (Kay 2015), part of an extensive dispersal of mammals known as the Great American Interchange. Like other major seaway reconfigurations, the appearance of the landbridge between South and North America is likely to have changed ocean current circulation, which would have had an impact on global climate.…”