Fossil Finds near Lake Turkana Quiz

Answer: flat-faced

'Flat-faced' is an approximate translation of the Greek word 'platyops'. In this case it refers to the atypical smaller degree of subnasal prognathism - in English, that means that unlike most species, its jaw doesn't jut out much beneath the nose.
Kenyanthropus platyops was discovered by Kenyan research assistant Justus Erus, a member of Meave Leakey's team, and excavated in 1998 and 1999 at Lomekwi, in the Nachukui Region just west of Lake Turkana.

Answer: Australopithecus afarensis

Despite widespread scientific debate, Meave Leakey and her team hold fast to their belief that Kenyanthropus platyops and Australopithecus afarensis existed in the same time period and probably even co-existed geographically, given the number of Australopithecus afarensis finds in northern Kenya and southern Ethiopia.
Dissenting scientists believe that Kenyanthropus platyops is merely a variant of Australopithecus afarensis, and that the two are the same species. Meave Leakey and her supporters point out that K. platyops has small earholes, small molars, and a relatively flat face, making it quite different to its Australopithecine friend.
K. platyops lived 3.5 - 3.2 million years ago, while A. afarensis lived 3.9 - 3.0 million years ago. Both dates are, of course, approximate.

Answer: average body weight

The average body weight estimate for male specimens shows
that Australopithecus anamensis was about twenty percent larger than Australopithecus afarensis. The body weight estimate of the A. anamensis is about 55-58 kg. but is only 44.6 kg. for A. afarensis. Remember that these species stood less than a metre high.
A. anamensis lived approximately four million years ago.

Answer: The male teeth

The only area in which paleontogists have been able to establish sexual dimorphism in Australopithecus anamensis is in their teeth. Those of the male A. anamensis are decidedly larger than those of the female. In the case of the humerus and the tibia, only one of each has been recovered, therefore it is so far impossible to compare a male and a female sample.

Answer: Huge teeth

Megadontia meens huge teeth. Paranthropus boisei has the largest teeth found in any hominid skull, with teeth the size of a full-grown gorilla's. Full-grown gorillas weigh ten times as much as Paranthropus boisei did. Its molars are 2 centimetres in diameter, whereas an average human adult has molars a little under 1 centimetre in diameter. P. boisei, which has been uncovered at Lake Turkana sites, is usually called a hyper-robust species, and it lived approximately 2.3 - 1.2 million years ago.

Answer: The Black Skull

The fossil was called The Black Skull because mineral uptake while the skull was being fossilized gave the skull a bluish-black colour. It has the smallest cranial capacity ever found in an adult hominid specimen, meaning that it had a very small brain. Australopithecus aethiopicus was extremely prognathous, meaning that its jaw jutted out very far, and is extremely primitive.

The Black Skull has been dated to approximately 2.5 million years ago.

Answer: volcanic rock

Homo habilis used pieces of volcanic rock to make his tools. He chipped pieces away from the rock to reveal sharp, jagged edges. These are called Oldowan stone tools, and are so named after Olduvai Gorge, where these tools were first discovered. Since their first discovery, examples of these tools have been found as far north as Ethiopia, and have been recovered at Koobi Fora, near Lake Turkana in Kenya. Outside of Africa, Oldowan tools have been discovered in Europe and Asia.

The oldest stone tools found to date have been in the Hadar Valley of Ethiopia, and were 2.6 million years old. Homo habilis lived approximately 2.6 - 1.8 million years ago.

Answer: Lake Malawi

The mandible was found near Lake Malawi, in the small southern African country of Malawi, and was obviously Homo rather than Australopithecus, due to its lack of robustness and its small cheek teeth. Homo rudolfensis is thought to be around 1.9 million years old.

Answer: of septicemia from a tooth infection

Turkana Boy, for that is who this skeleton is, is Homo erectus, and was approximately 11 or 12 years old when he lay down to die by the edge of Lake Turkana 1.6 million years ago. Close examination reveals staining on his mandible [jaw], which means that it is possible that after a new tooth had broken through - Turkana Boy was still growing new teeth - an infection had set in and, untreated, had turned to septicemia. Records from fifteenth century London, interestingly enough, show that septicemia from tooth infections were the second most common cause of death after the plague, so maybe it was also a killer millions of years ago.

There were no gnawing marks on his bones, so the team knew that the boy had not been attacked by an animal. Homo erectus lived approximately 1.8 - 1.0 million years ago.

Answer: his height

The height was the real surprise for the paleoanthropologists, second only to the beautifully preserved skeleton, found near Lake Turkana. The skeleton of the adolescent male was approximately 5 feet 6 inches tall, which suggests that as a man he would have been over six feet tall. All previous estimates of early man had placed our Homo erectus ancestors around five feet tall, at best. Turkana Boy's bone structure also suggested that he would have been heavily muscled and stockily built, as well.

Sources:
Leslie Aiello & Christopher Dean, 'Human Evolutionary Anatomy'
Donald Johanson & Blake Edgar, 'From Lucy to Language'
Richard Leakey & Roger Lewin, 'Origins Reconsidered'
www.modernhumanorigins.net
www.pbs.org/wgbh/evolution/humans/humankind