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When the 3 and 1/2 foot Homo floresiensis was discovered and the age of the new species correlated with the the same time Neanderthals were dying in Europe and humans colonized Asia a lot of arms and voices were thrown in the air. People questioned the validity a new species, so different, so small… A “Hobbit.”

A lot of people speculated them simply a modern human subjected to dwarfism. Founder effects. Others looked at the characteristics in its skeleton and questioned it a Homo erectus relative. Some of those theories literally fall short as Homo erectus made it to Java, but not the island of Flores.

hobbit2

A new paper in the Journal of Human Evolution which came out a couple days ago suggests it may have branched off from the human lineage even earlier than that. The new paper widens the range of physical traits to include the crania, mandibles, dentition, and postcrania of Homo and Australopithecus. If you look at their data set, the authors impressively measure, collect and compare over 130 skeletal characteristics. It is dizzying to even keep track on their comparative anatomy. Their conclusion is that H. floresiensis is an early Homo lineage; either a sister to H. habilis alone or to a clade consisting of at least H. habilis, H. erectus, Homo ergaster, and H. sapiens.

Figure 1 & Figure 2

Figure 1. Affinities of Homo floresiensis based on phylogenetic analyses of dataset A (intraspecific variability coded as new state; see main text). Homo rudolfensis is excluded. Note that while support for many nodes is not strong, most alternative hypotheses for the position of H. floresiensis can be rejected (see Table 3A). (A) Parsimony: majority-rule consensus of bootstrap trees. Numbers at nodes refer to bootstrap frequency. (B) Parsimony: shortest tree, length ¼ 584. Numbers at nodes refer to branch (Bremer) support. (C) Bayesian: majority-rule consensus of sampled post-burnin trees. Numbers at nodes refer to posterior probability
Figure 2. Affinities of Homo floresiensis based on phylogenetic analyses of Dataset B (intraspecific variability coded as polymorphism, i.e., multiple states; see main text). Homo rudolfensis is excluded. Note that while support for many nodes is not strong, most alternative hypotheses for the position of H. floresiensis can be rejected (see Table 3B). (A) Parsimony: majority-rule consensus of bootstrap trees. Numbers at nodes refer to bootstrap frequency. (B) Parsimony: strict consensus of three shortest trees, length ¼ 274. Numbers at nodes refer to branch (Bremer) support. (C) Bayesian: majority-rule consensus of sampled post-burnin trees. Numbers at nodes refer to posterior probability

These results raise up three outstanding issues. Firstly, H. floresiensis is a long-surviving relict of an early (>1.75 Ma) hominin lineage. Which means, secondly, there is an earlier unknown migration out of Africa, way earlier than we expected.

Lastly, we currently do not known if Homo habilis was an early human or a late Australopithecus relative.  Homo ergaster, an older species than habilis and erectus may instead be the first “human” species, meaning that, if you’re of the school of thought that habilis is too primitive to be considered human, the Hobbit likely was, too. Either way, the Hobbit’s primitive features make it in-line with a  habilis relative rather than a descendant, much in the same way that humans and Neanderthals were closely related but descended from a shared ancestor. But who that ancestor was, is currently not known.

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