RESUMEN
We review here the molecular data that bear on and provide a framework for interpreting hominoid relationships. Man is shown to be most closely related to chimpanzees and gorillas among extant hominoids, with the orang-utan more distantly related to them and the gibbons more distantly still. A fossil ape, Sivapithecus meteai, shares several characters with the orang-utan and is thus probably related to it. S. meteai is part of the Middle Miocene Sivapithecus-Ramapithecus species complex, and if this group forms a valid clade then Ramapithecus must also be considered as being more closely related to the orang-utan than to man. The date of divergence of the orang-utan from the African apes and man is suggested by fossil and molecular evidence to be 10 +/- 3 Myr ago.
Asunto(s)
Evolución Biológica , Fósiles , Hominidae/genética , Paleontología , Pongo pygmaeus/genética , Animales , Humanos , Primates/genética , Especificidad de la EspecieRESUMEN
The nature of human evolution has been viewed recently as a specific example of a more general model of evolution termed "punctuated equilibrium". The characteristics of this model are long periods of little or not evolutionary change (stasis) interspersed with periods of rapid (punctuated) morphological change. Careful analysis of the hominid fossil record over the past 4.0 million years, however, suggests no well documented examples of either stasis or punctuation. The evidence for the evolution of the hominid lineage is most reasonably interpreted by a model of more gradual change with periods of varying rates of evolution.
Asunto(s)
Evolución Biológica , Haplorrinos/anatomía & histología , Antropometría , Fósiles , Historia Antigua , Humanos , Cráneo/anatomía & histología , Factores de TiempoRESUMEN
Genetic variation at 16 protein and enzyme loci in Ceropithecus aethiops and several other primate species has been surveyed, using cellulose acetate microelectrophoresis. Resolution of several standard variant proteins is comparable to that achieved on starch gel or polyacrylamide gel. Although both intraspecific and interspecific variation was observed for some loci, the data generally support the concept that extracellular proteins are more likely to be polymorphic within a species, while intracellular proteins generally vary between species, if at all. These methodologies are particularly appropriate for screening multiple-locus variation in large numbers of samples; their relevance to studies of molecular evolution and evaluation of theories of kin selection is discussed.
Asunto(s)
Cercopithecus/genética , Chlorocebus aethiops/genética , Hominidae/genética , Macaca/genética , Pan troglodytes/genética , Polimorfismo Genético , Animales , Evolución Biológica , Electroforesis en Acetato de Celulosa , Enzimas/genética , HumanosRESUMEN
We report here the results of comparative immunological and electrophoretic studies of the serum proteins of the New World monkeys. Specifically, we find that the New World monkeys share a long period of common ancestry with the Catarrhini and that the divergence between these two groups occurred some 35-40 million years ago. The extant New World monkey lineages are then seen as sharing a long period of common ancestry subsequent to that divergence, with their radiation beginning in the early Miocene. We see seven distinct lineages stemming from this radiation: (1) Aotus, (2) Callicebus, (3) Cebus, (4) Saimiri, (5) Ateles-Lagothrix-Alouatta, (6) Pithecia-Cacajao and (7) Callimico-Callimico with Cebuella-Saguinus-Leontideus. Within those Ateles with Lagonthrix, and Callimico with Callithrix-Cebuella form further subgroups. The marmoset radiation appears to have begun some 7-10 million years ago.