The History of Our Tribe Hominini Textbook Part IV Pleistocene Epoch Chapter 32 Homo floresiensis

32 . Homo Homo ( kya ) human I Flores ) Figure By wiki File Restoration model . 189 SITES Liang cave , Flores , Indonesia PEOPLE Mike Figure Liang Cave . Homo cave by is licensed under . INTRODUCTION The material assigned to the species Homo comes only from the cave site of Liang ( see ure ) on the island of Flores in Indonesia ( see Figure ) Because of its diminutive size , the new species took the world by storm when it was discovered in 2003 by Mike and his team . While tools to the species have been dated to almost 100 kya , skeletal remains are dated to as young as 18 kya and as old as kya ( Brown et al . 2004 ) et al . 1998 ) had previously discovered a much older site ( 840 kya ) that they attributed to tus , but no associated skeletal material was found . Thus the ancestor of may have arrived much earlier . 190 The History of Our Tribe

PHYLOGENY While there is controversy ( see PHYSICAL CHARACTERISTICS below ) surrounding this strange species , is thought to have descended from a group of erectus that traveled across the sea from mainland Asia . Once there , they adapted to the island via a process known as insular or island dwarfism . Large mammalian species that become isolated on islands tend to decrease in size over time ( as opposed to reptiles and small mammals that may increase in size ) as smaller individuals require less food and thus have a better chance of survival and reproduction , when faced with limited space and resources and low risk of predation . However , komodo dragons were present . A dwarf ( a relative of the Asian ) also inhabited the island and served as a prey species , as evidenced by juvenile bones with signs of butchering . In addition , modern pygmy human groups inhabit tropical rainforests where small body size is thought to possibly be adaptive for traveling through the tangled interior . Though short , they have low mass relative to surface area and relatively long limbs and extremities just like tall peoples of East Africa ( the ) to reduce metabolic heat and maximize cooling via sweating . The may have until 12 kya when a volcanic eruption may have caused their extinction , as well as that of the dwarf . Since Flores was not inhabited when discovered by Portuguese traders in the century , they may never have coexisted with modern humans ( Wikipedia contributors , Figure Flores Island in red . ID Flares by is in the public domain . DISCOVERY AND GEOGRAPHIC RANGE As mentioned , there is only one site on Flores where material has been found , Liang cave . Mike and his colleagues are credited with the discovery of this species that is so recent in time , the skeletal elements are not even fossilized ( Brown et al . 2004 ) Material from nine individuals has been recovered . The only complete skull , is from a adult female for which they have material as well . Nicknamed The little lady of Flores or Flo , she serves as the type specimen for the species ( Brown et al . 2004 ) PHYSICAL CHARACTERISTICS At only ( tall and ( is very small relative to erectus , falling at the low end of habilis . Even more incredible is her brain size of 380 . Yet her quotient is estimated at . When compared with the brains of erectus and at and at , her brain is not as small as it first appears . Other aspects of morphology are primitive to Homo species , such as its hip and limb characteristics , especially in the shoulder 32 . Home I 191

Figure Homo . Homo by Ryan Somma . is licensed under and wrist . characteristics ( see Figure ) are consistent with Home status , most closely aligning with erectus , including multiple mental ( small holes in the mandible through which multiple branches of the trigeminal nerve exit the bone to innervate the face ) whereas we have only one ( Brown et al . 2004 et al . 2005 ) the limb bones were robust and the feet were flat and relatively large ( et al . 2008 ) While body size is expected to decrease via insular dwarfism , brain size does not usually keep pace and thus can be used to support a case for dwarfism . Some researchers have argued that is a modern human with microcephaly , an ontogenetic disorder that results in an exceptionally small brain and cranium and greatly limited cognitive capabilities . However , primitive skeletal characteristics , the complexity of the remains , and the size of an important association area of the prefrontal cortex ( Falk et al . 2005 ) do not support the microcephaly argument . Review of Primitive Characteristics hip and upper limb morphology , especially shoulder and wrist components . Review of Derived Characteristics Dwarfism . Brain reduction without apparent loss of cognition . 192 The History of Our Tribe

ENVIRONMENT AND WAY OF LIFE Flores was primarily tropical forest during the time that occupied the island . Tropical forests , while rich in biodiversity , are poor human habitats due to a low density of food species . In other words , on average you will find many different species of plants and animals per unit area but not very many of each . Compounded by the small area of the island , dwarfism and complex culture likely explain the survival of the species . They made and used tools , as evidenced by the presence of sharpened tools , prepared cores for the production of tools , from their manufacture , anvils , along with faunal remains from a variety of species , such as , komodo dragons , rats , and bats ( et al . 2005 ) Their tools were small , compatible with their small body size . Burnt bones , rock , and a possible hearth consisting of a circle of fired rocks show that they made use of fire . Large predators and scavengers like komodo dragons are known to clean up anything that dies , often without a trace . It is thus lucky that we have some remains of . Figure Homo encounter by Taylor . 32 . Homo 193