I do not think so, based upon my perception of the evidence. At least not in our more distant past, before Homo sapiens.
Homo floresiensis and the Origins of the Genus Homo
Introduction - From a cladistic view, primitive characters do not provide evidence of close affinities. In evolution it is commonly seen that adaptive radiations occur not from highly derived / specialized forms, but instead from marginal conservative ancestral like forms. Such radiations usually are driven by environmental changes causing extinctions, such as the retreat of tropical rain forests around 8 million years ago in Africa and Asia. The fossil record for Hominins is poor in general. Arboreal mammals in general are biased against in the fossil record due to the low preservation potential of forest soils. In this article the author argues that it is more correct to think of African apes as being evolved / derived from the genus Homo than visa versa. And African apes being more derived than Homo floresiensis relative to an unknown Asiatic common ancestor of both lineages.
That modern humans are among all extant primates most closely related to African apes is well established by genetic evidence. There does not exist fossil or genetic evidence firmly establishing candidates as direct ancestors of humans in Africa after the drying period around 8 million years ago, which saw the retreat or tropical forests in Africa and Asia, up until the emergence of Homo sapiens and close relatives around one million years ago in Africa. This fact suggests that Asiatic origins for humans should be further explored for the period of around 8 to 3 million years ago. The author here uses the term Asiatic to include any unknown fossil humans in Australia or Europe as a complex more connected Asia than Africa.
If the common origins of African apes and humans is in Asia, then the ancestral forms would probably have had the capability to cross more arid terrains to return to Africa. The best candidate for such an immigrant is an ancestral form of Homo floresiensis with H. floresiensis proposed as a remnant population of such a group in the refugial environment of Flores Island.
If this is the case, then H. floresiensis likely could have walked to Flores Island from the Asiatic Mainland about 5 million years ago (Metcalfe 2007). Thus eliminating any need for a difficult journey from Africa, with no fossil record of such an event or African ancestral form. And no need to invoke Island waifs, which would be troubled by genetic funneling over more than 700,000 years on Flores Island as indicated by the fossil record (van den Bergh et al 2016).
Compare the skull of Homo floresiensis to the partial skull of Lufengpithecus lufengensis from China near the end of the Miocene (Xueping et al 2013). It appears much more similar and less derived compared to H. floresiensis, relative to any living or fossil ape not assigned to the genus Homo. The similarities appear to much to be explained by neotonous characters in H. floresiensis or convergence. In reference to Lufengpithecus "representing the last common ancestor of all extant great apes" (Andrews 1992). With the striking similarity to H. floresiensis, this suggests that H. floresiensis is conservative, relative to other apes, in facial morphology.
Gigantopithecus has a fossil record extending back 9 million years, much farther than any fossil African ape proposed to be near the ancestry of Homo. Gigantopithecus shows affinities in dental morphology to humans (or convergence), and is of uncertain placement relative to Homo and Pongids.
Could ALL fossil and extant apes (except Gibbons), be morphologically derived relative to Homo floresiensis, compared to the common unknown Asiatic ancestor of apes and Homo? Towards the end of the Miocene, as apes were retreating in Africa and going nearly extinct in Asia, could a diminutive small brained lineage of human like generalized apes have evolved in Asia?
Modern humans can be competent in all forms of locomotion seen in apes except knuckle walking, due to specialized and derived hands for tool manufacture and closed fist striking. Orangutans are fist walkers, modern humans can cover long distances over rough terrains as finger tip to palm walkers, similar to baboons. Modern humans are in all environments which apes can exist in, and have long distance locomotion in all environments which apes exploit, with the exception of arboreal canopies.
The known range of Homo Floresiensis is about 700,000 years ago (van den Bergh et al 2016) to about 50,000 years ago, the earlier forms being about 25% SMALLER than the younger forms. This is a small time frame relative to the development of an hypothetical Homo floresiensis like Asiatic ancestor around 5 to 7 million years ago. Different populations and individuals at any one time could have varied in size. But it does indicate they were not getting any smaller over time on Flores Island.
Ancient humans who adapted to semi arid conditions such as on Flores 700,000 years ago (van den Bergh et al 2016), or even to arid conditions, might have benefitted from small body size. Roving in bands much like extant apes, they could have defended themselves fairly well from carnivores and other apes by stone throwing and darting up trees or rock outcrops. They would have been opportunistic feeders with a generalized conservative phenotypes allowing them to exploit varying environments, and move reasonably well over all types of terrains. Jacks of all trades and masters of none, survivors in times when most other apes became extinct in Asia.
Protohomos were small brained relative to modern humans as other apes, nothing special or God like about them. As they repopulated Africa and parts of Asia with apes, they reached pockets of forests and partly forested areas by then without African apes or Gibbons in Asia. Entering new environments they specialized and gave rise to multiple branches of specialized more derived apes in Africa terminating with the Australopithecines. Protohomos enjoyed an adaptive radiation in Africa and Asia. Much as with other similar adaptive radiations by conservative stem groups, fueled by an extinction event among apes and resulting pockets of forested /partly forested areas unpopulated by apes. And by exploitation of new environments culminating with the exploitation of colder environments than ever before exploited by apes, in the Pleistocene.
"the LB1 specimen belongs to a clade that can be named Homo erectus" (Valery et al 2016). The author agrees, but suggests that the Homo erectus clade extends back some 5-8 million years in Asia. In cladistics you do not stop being something you once were. Thus, extant African apes and their fossil relatives are also members of the Homo erectus clade, just highly derived members. "Ardipithecus ramidus thus indicates that the last common ancestors of humans and African apes were not Chimpanzee like" and "Overall Ardipithecus ramidus demonstrates that the last common ancestors of humans and African apes were morphologically far more primitive than anticipated, exhibiting numerous characters reminiscient of middle and early Miocene hominoids (White et al 2009).
Protohomos may have carried stones with them as a sort of tool kit, through use or selection these could have had sharp edges. They also could have been used as striking or throwing weapons in arboreal environments. They may have been conservatively monogamous as are gibbons. Thus their teeth were smaller and jaws weaker than in many of the apes they gave rise to. They did not have as much need for strong sexual dimorphism to defend themselves from predators, or to crack nuts of fruit pits with their teeth. They would not have modified stone tools, not had language beyond that of extant apes or controlled fire. They would have looked more like extant humans than apes and been hairy. And have lived in very similar manner to extant apes and monkeys. Like baboons being able to exploit multiple types of environments, such as moving through braided environments along coastlines with nearby mountains.
"Therefore LB1 offers the most complete glimpse of a bipedal hominin foot that lacks the full suite of derived features characteristic of modern humans and whose mosaic design may be primitive for the genus Homo, these new findings raise the possibility that the ancestor of H. floresiensis was not Homo erectus but instead some other, more primitive hominin whose dispersal into southeast Asia is still undocumented.". (Jungers et al 2009).
Alan D VanArsdale April 7, 2017
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