New Species of Early Human Is Even Smaller Than the 'Hobbit'
Os antigos ossos e dentes de um parente humano previamente desconhecido - um que era ainda menor do que o chamado Hobbit - foram descobertos no fundo de uma caverna em uma ilha nas Filipinas.
A nova espécie é chamada Homo luzonensis em homenagem a Luzon, a ilha onde os seres misteriosos viveram durante a época do Pleistoceno, há mais de 50 mil anos. Com menos de 4 pés (1,2 metros) de altura, H. luzonensis é o segundo anão humano conhecido em registro, sendo o primeiro Homo floresiensis, também conhecido como o Hobbit, cujos restos mortais foram encontrados na ilha indonésia de Flores em 2004.
A nova espécie é chamada Homo luzonensis em homenagem a Luzon, a ilha onde os seres misteriosos viveram durante a época do Pleistoceno, há mais de 50 mil anos. Com menos de 4 pés (1,2 metros) de altura, H. luzonensis é o segundo anão humano conhecido em registro, sendo o primeiro Homo floresiensis, também conhecido como o Hobbit, cujos restos mortais foram encontrados na ilha indonésia de Flores em 2004.
Mas embora H. luzonensis seja curto como o hobbit, ele compartilha características com vários outros antigos parentes humanos; tem ossos curvos de pés e dedos, como o Australopithecus (um gênero que inclui a famosa Lucy); pré-molares que possuem características semelhantes às encontradas no Australopithecus, Homo habilis e Homo erectus; e pequenos molares que se parecem com os humanos modernos, ou Homo sapiens. [See Photos of the Newfound Ancient Human Relative Discovered in Philippines]
"Esses elementos fósseis mostram uma combinação de características morfológicas [estruturais] que não são vistas em outras espécies do gênero Homo, indicando assim uma nova espécie, que denominamos Homo luzonensis", disse o pesquisador-chefe Florent Détroit, paleoantropólogo Museu Nacional de História Natural, em Paris, disse em um comunicado que o museu forneceu aos repórteres.
It took years to find the H. luzonensis remains. After scientists found a 67,000-year-old metatarsal,
or toe bone, in Luzon's Callao Cave in 2007, they scheduled follow-up
excavations in 2011 and 2015. In total, they uncovered 13 fossil bones
and teeth that belonged to at least two adults and one child, including
two hand bones, three foot bones, a thigh bone and seven teeth. One of
these fossils dated to 50,000 years ago, indicating that H. luzonensis lived at the same time as other human lineages, including H. sapiens, Neanderthals, Denisovans and H. floresiensis, according to the study, which was published online today (April 10) in the journal Nature.
What did it look like?
It's difficult to say what H. luzonensis looked like "because it
is very difficult to tell from the elements we have," Détroit said.
Given that the teeth are very small — even smaller than those of H. floresiensis — it's likely that the newfound species was small bodied, he said. Moreover, the curved toe and finger bones suggest that H. luzonensis was adept at climbing trees as well as walking upright on the ground. [Image Gallery: A Real-Life Hobbit (Homo Floresiensis)]
Granted, the genus Homo became a strict bipedalist (meaning it walked on two feet) about 2 million years ago, so "we are certainly not pretending that H. luzonensis was 'back to the trees,'" Détroit said. Rather, it's possible that this feature arose because H. luzonensis lived on an isolated island, he said.
"But it is then a very interesting question to address," Détroit said.
"If they were strict bipedal like all members of the genus Homo,
did such primitive features influence [or] change their bipedal gait or
not? But it is still too early to answer, we need to work on that."
Countless other mysteries are left unresolved, including where H. luzonensis fits
into the human family tree and how these little human relatives reached
Luzon, which has been an island (no land bridge) for at least 2.6
million years. [Image Gallery: A Real-Life Hobbit | Homo Floresiensis]
Evidence of ancient animal butchery on Luzon dating to 700,000 years ago suggests that "some sort of Asian Homo erectus
(maybe from China) successfully crossed the sea and settled on Luzon
Island, where they subsequently underwent the effects of 'insular
endemism,' which resulted into H. luzonensis," Détroit said.
"But this is very speculative, I might be wrong on one (or several)
aspects of this simple scenario. We will work on this in the future."
Détroit noted that the scientists were unable to extract any DNA from the bones,
in part because the wet and warm climate of the Philippines doesn't
help preserve genetic material. However, it's possible that proteins
could be extracted from the remains, and those could shed light on the
family tree question, the researchers said.
If anything, this previously unknown species shows the evolutionary
complexity of hominins — bipedal primates that have increased brain
size, which includes humans, our ancestors and our close evolutionary
cousins, Détroit said.
Outside thoughts
The study reports on a "remarkable discovery" that will "no doubt ignite plenty of scientific debate
over the coming weeks, months and years," Matthew Tocheri, Canada
Research Chair in Human Origins and an associate professor of
anthropology at Lakehead University in Ontario, Canada, who wasn't
involved in the study, wrote in an accompanying perspective in the
journal Nature.
For instance, anthropologists are always skeptical of newly discovered
species that are based on just a few fossil specimens. But while the
sample of remains of H. luzonensis "is not great," the authors of
the new study present a compelling case that the dwarf is a new
species, Huw Groucutt, group leader of the extreme events research group
at the Max Planck Institute for Chemical Ecology in Jena, Germany, told
Live Science in an email.
These findings show that the "study of human evolution
has been based far too much on a few small and unusual areas (like
Europe and South Africa)," Groucutt said. "This finding shows how many
surprises remain. And how human evolution has led to all of these
diverse forms of hominin."
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