A complete skeleton of the giant South American primate Protopithecus

Abstract

A complete skeleton of a large-bodied New World monkey has been found in Pleistocene cave deposits in the Brazilian state of Bahia. It demonstrates an unprecedented combination of body size, locomotor and cranial morphology. Skeletal features indicate an animal of approximately 25 kg, more than twice the mass of any living South American monkey. We refer the specimen to Protopithecus brasiliensis Lund, 1838, a large Pleistocene primate originally represented by only a proximal femur and distal humerus. The skeleton resembles species of two distinct New World monkey lineages. The cranium is modified for an enlarged vocal sac typical of living howler monkeys, and the postcranium includes suspensory and brachiating components of locomotion as seen in living spider and woolly spider monkeys. This skeleton confirms that adaptive diversity in neotropical primates was greater in the recent past, and that current interpretations of how their distinctive adaptations evolved should be revised.

Marmoset Misconceptions

“…These include Cebus, Saimiri, callitrichines, and atelines (Kay 1990(Kay , 1994Rosenberger & Strier, 1990;Ford & Davis, 1992;Rosenberger, 1992;Cartelle & Hartwig, 1996). For example, Ford & Davis (1992:438-439) surmise that over the course of platyrrhine evolution capuchin monkeys have "nearly tripled in body size .. .independent of all other New World monkey lineages."…”

“…Saimiri, in contrast, has probably undergone a significant body size reduction in comparison to its nearest early Miocene fossil relative Dolichocebus (Rosenberger, 1990). Relatives of spider and howler monkeys were, in the recent past, twice as large as any remaining alive today (Cartelle & Hartwig, 1996;Hartwig & Cartelle, 1996). Although it is unclear how frequently increases and especially decreases in body size have occurred in platyrrhine evolution, these events appear to have played a major role in shaping the reproductive, mating, and social systems of New World primates (Ford & Davis, 1992;Martin, 1992;Garber, 1994).…”

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

“…but do not resolve the timing of cladogenesis within Atelidae (Hartwig, 1993;Cartelle and Hartwig, 1996;Hartwig and Cartelle, 1996;Jones, 2008). C. Cebidae -The extant family Cebidae includes two subfamilies, the Cebinae (Cebus, Saimiri and Aotus) and the Callitrichinae (tamarins and marmosets).…”

Primate evolution: A biology of Holocene extinction and survival on the southeast Asian Sunda Shelf islands

“…Many studies have indicated that taxa of large body size can be prone to extinction, especially at the hands of humans (Brown, 1971;Caughley and Gunn, 1996;Godfrey et al, 1997;Harcourt, 1999;Hartwig and Cartelle, 1996;Jolly, 1986;Martin, 1984;McKinney, 1997;Richard and Dewar, 1991;Vermeij, 1986). Because so many aspects of a species' biology correlate with body size (CluttonBrock and Harvey, 1983;Jungers, 1985), several mechanisms for the correlation of probability of extinction with body size have been suggested.…”