Friday, May 8, 2009

Biological Parallels

I have been very interested in the discovery of Homo floresiensis since it hit the news a few years ago. Not only is this generally interesting to humankind in that another species of man has been added to the family album, but it is specifically interesting to those of us interested in unknown primates because of the persistent rumors and sightings of the orang pendek from this part of the world.

In case you haven't heard of the orang pendek (also known as the sedapa), it is basically a bigfoot-like creature, but one that stands four or five feet tall. A biologist named Debbie Martyr has been trying to study this creature for several years on the island of Sumatra and has had some limited success, including a couple of blobsquatchy photos of the critter, multiple sightings, and a couple footprint casts.

Debbie Martyr holding a footprint cast

There has been a debate about Homo floresiensis since its discovery. Humans don't seem to be very comfortable with our closest evolutionary relatives, and usually try to distance ourselves from them, or to at least elevate our own species so as to seem different and special. This is leftover residue from an idea called The Great Chain of Being, which has colored the perceptions of scientists for hundreds of years.

It was hypothesized that Homo floresiensis was a "normal" human with some sort of pathological condition. This theory has now been put to bed by studying the foot bones of the hobbit.

While reading this article, I was frequently reminded of the numerous times I have listened to Dr. Jeff Meldrum speak about the foot anatomy of the sasquatch. The hobbits' foot shows many of the same characteristics that Meldrum has hypothesized can be found in the sasquatch foot.

Footprint cast attributed to the orang pendek

Hobbits were, like sasquatches are, flat-footed. This will naturally result in increased flexibility of the midtarsal joint. The article speaks of the length of the hobbits' toes, and Meldrum points out that sasquatch toes are relatively long and flexible, with about as much gripping ability as our smaller fingers.

Hobbits, like sasquatches, were not well adapted for long distance running either. While sasquatches do run at great speeds (they have been observed running at over 35 miles per hour), their overall anatomy (great size, hair covering, foot structure, etc...) is clearly not designed for more than sprinting over relatively short distances. In fact, Dr. Grover Krantz suggested that while Homo erectus lost its hair for better temperature regulation while persistence hunting, Gigantopithecus (that lived at the same time and place as Homo erectus, and is hypothesized as being the ancestor to modern day bigfoots) would have exploited different food sources and would have thus kept their hair covering.

For me, one of the most compelling aspects of bigfoot research is how nicely the data fits together. One can see the anatomy of other apes in the anatomy of the sasquatch. Now we are seeing parallels in another bipedal hominid from the other side of the world. This particular hominid could very well have relic members of its species walking around the jungles of Indonesia today. I would argue that the more congruent the data is between the sasquatch and other apes, particularly the bipedal ones, the more compelling that data should be for scientists.

That's where we, the amateur bigfooters, come in. It's our job to generate a significant body of compelling data for scientific review that will turn the heads of academics, one by one, until there is a coherent effort to study and protect these creatures.

So, get into the woods and get some evidence! Oh yeah, and enjoy the article...

The foot that may prove 'hobbits' existed
Unusual features suggest that remains discovered on Indonesian island did belong to new human species

By Steve Connor, Science Editor
Thursday, 7 May 2009

The 'hobbit's' foot bones

A miniature species of extinct humans, nicknamed "hobbits", possessed unusual anatomical features explained by their complete isolation from the rest of humanity for thousands of years on their remote island home in Indonesia, studies have found.

The tiny people, who grew to an adult height of no more than three feet, astounded scientists in 2004 when a skull and partial skeletons were unearthed from a cave on the island of Flores. Radiocarbon dating suggested that the species, Homo floresiensis, had lived in and around the cave for tens of thousand of years before dying out about 17,000 years ago.

The latest research into H. floresiensis has found that they were flat-footed, long-toed creatures who could walk easily on two legs but would have found it difficult to run at speed. A separate study suggests that their very small heads, which were perfectly in proportion to their bodies, were the evolutionary outcome of living on such a remote island for so long.

Two studies published in the journal Nature also cast further doubt on the idea that the hobbits were ordinary people suffering from some kind of pathological condition, such as microcephaly – when the skull fails to grow normally. Many scientists believe there is now little doubt that the hobbits were indeed a human species who had evolved as a result of island dwarfism, when larger animals gradually become smaller over the generations.

"That evidence has been overwhelming for some time now. Our study provides additional and unequivocal confirmation that we're dealing with a new species. The pathology debate is officially over," said Professor Bill Jungers of Stony Brook University in New York, who led the study into the hobbit's foot bones. "Their big toe was surprisingly short and more similar to a chimpanzee's in relative length than to humans.

"However, like chimpanzees again, the free parts of the lateral toes were relatively very long and the bones within were curved, whereas human toes in this region are short and straight," Professor Jungers said.

The investigation of the hobbit's foot bones also revealed that the miniature humans lacked an arch. In other words, they were flat footed. "They still walked just fine despite having relatively long feet and funny proportions, but they needed to lift their feet a little higher off the ground to clear their toes, possibly by flexing their ankles or knees more. They were designed quite adequately for walking, but were poorly adapted for long-distance running," Professor Jungers said.

A range of small stone tools found alongside the bones suggest that the hobbits hunted and butchered local animals that lived on the island at the time, such as pygmy elephants, giant rats and reptiles, such as the Komodo dragon. But their ancestral origins remain a mystery.

The long toes of H. floresiensis suggest they could be the direct descendants of a hominin similar to an early human ancestor such as H. habilis, rather than the more recent H. erectus, a species known to have migrated out of African long before the migration of our own species, H. sapiens.
Alternatively, the hobbits may be the descendants of a dwarfed H. erectus that not only underwent a miniaturisation of its body, but reverted to more primitive features. Professor Jungers said that both scenarios are possible, although at present he favours the idea that the hobbits were descended from a bipedal hominin that had escaped Africa before H. erectus.

A separate study by researchers from the Natural History Museum in London investigated the problem of the hobbit's very small skull and brain by comparing it with the skull of extinct pygmy hippos that lived on the island of Madagascar. Like the hobbit, the hippo's skull had become smaller over time and in perfect proportion to the miniaturisation of its body.

Eleanor Weston, who led the study, said that the hippo shows for the first time that island dwarfism results in the miniaturisation of skull and brain seen in the hobbit. Dr Weston said: "Whatever the explanation for the tiny brain of H. floresiensis relative to its body size it is likely the fact it lived on an island played a significant part in its evolution."

A key difficulty with the idea that the hobbits are a new species of human is that their brains are so small. How could a brain about the size of a grapefruit provide the intelligence to make and use the exquisitely carved stone tools found alongside the bones of H. floresiensis?

Adrian Lister and Eleanor Weston of the Natural History Museum in London believe that their expertise in studying "island dwarfism" in other animals has resolved the problem. Their study of an extinct species of dwarf hippo on the island of Madagascar showed for the first time that skull and braincase do indeed become smaller in direct proportion to the miniaturisation of other parts of a dwarfed body. In other words, the exceptionally small head and brain of H. floresiensis can be explained by evolutionary pressures resulting from living on an island, rather than the result of some kind of medical condition. And they seemed to have lived happily with small brains.

Island dwarfism is a well-known phenomenon. Extinct pygmy mammoths have been found on Wrangel Island in Siberia, along with dwarfed elephants on Mediterranean islands. Dwarfism is a way of surviving the limited resources of an isolated habitat, Dr Weston said.

"We found that the brain sizes of extinct dwarf hippos were up to 30 per cent smaller than you would expect by scaling down their mainland African ancestor," said Dr Weston. "If the hippo model is applied to a typical H. erectus ancestor, the resulting brain capacity is comparable to that of H. floresiensis."

An artist's rendition of the hobbit

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