Name: answers human Evolution 6 Year 13 Science 2015

Many shapes, regular shapes

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Many shapes, regular shapes,

12. How were Mousterian tools made?

Made from flakes, finely worked

13. What were Mousterian tools used for?

Specific purposes, scrapers, spear tips, axe heads

Neanderthals disappeared from the fossil record about 25 000 years ago. It is likely to be a combination of factors:

  • the end of the ice age saw a rise in temperatures in Europe – this may have exceeded the tolerance of cold-adapted Neanderthals

  • rising temperatures caused changes in vegetation with forests becoming grasslands – this habitat change may have reduced success of hunting

  • change in habitat and rising temperatures caused reduction then extinction of food sources

  • niche overlap with Homo sapiens leading to extinction of Neanderthals – outcompeted for resources

14. When did Neanderthals disappear?

About 25 000 years ago

15. What evidence is there to support that?

No fossils found after that

16. Why did Neanderthals disappear?

Raising temperatures led to demise of resources, not adapted for heat, loss of habitat, competition with Homo sapien

Homo floresiensis – ‘hobbit’

  • ancient skeleton found in 2003 on isolated island of Flores in Indonesia

  • 1 metre tall

  • small brain – 380 cm3

  • other group found

  • lived 80 000 to 20 000 ya (possibly 12 000 ya)

  • co-existed with Homo sapiens

  • similar skeletons – just smaller – more in common with Homo erectus than modern humans

  • feet flat – could not walk fast

17. Describe a ‘hobbit’.

1 metre tall, small brain, flat feet

18. When did Homo floresiensis live?

Flores, island in Indonesia

  • upper Palaeolithic stone tools found with ‘hobbit’ remains

  • probably hunted co-operatively large prey

  • used fire for cooking

  • frontal and temporal lobes of brain were highly developed

  • structure of brain, not size, important in determining intelligence

  • no DNA analysis

Interpretation of Flores fossils is controversial

  • either they were a form of modern Homo sapien that developed a genetic disorder

  • or group of early humans who became isolated on Flores and developed dwarfism

19. Compare the skeletal structure of Homo neanderthalensis with that of Homo sapiens, accounting for differences.

H neanderthalensis was a robust type, having heavy skeleton – strong arm bones, barrel chested, short and stocky – powerful

H sapiens was a gracile form, having a lighter skeleton – thinner bones, taller and thinner, less powerful

Differences likely due to

  • climate in Europe and Africa – cold climate in Europe selected a shorter stockier form to conserve heat (small SA:V ratio) while hot climate in Africa selected a taller, lankier form to shed heat (high SA:V ratio)

  • lifestyle – Neanderthals hunted large game and killed with stabbing spears – those individuals that were stronger were more successful, so passed on their alleles for body type; Homo sapiens developed more refined, composite tools an did not have the same selection pressures for a powerful body type

20. Describe four differences that would identify a skull belonging to H. neanderthalensis and not to H. sapiens.

Larger cranial capacity, heavy brow ridges, occipital bun, lack of prominent chin

21. Give the significance of the presence of Broca’s area together with the FOXP2 gene in Homo neanderthalensis.

Indicated the ability to use language, so improved communication which would enhanced survival in many ways e.g. improved co-operative hunting

22. Scientists compared the amount of cutting edge that could be obtained from a given mass of rock, and the amount of work needed to produce a typical stone tool using two different stone age technologies.

Acheulean tools

(associated with Homo erectus)

Mousterian tools

(associated - Homo neanderthalensis)

Length of cutting edge produced from 500 g of stone

0.2 metre

1 metre

Number of blows needed to make typical tool



Example of each technology - axe

Use the information from the table to describe three trends in tool manufacture.

Length of cutting edge increases / number of blows increases / more precise or refined tools / more time devoted to making tools

23. Describe the lifestyle of Homo neanderthalensis, and account for

  • the presence of a large amount of meat in their diet

  • advances in their culture over that of Homo erectus

  • advantages of the movement of females from clan to clan

Neanderthals lived territorial groups of about 8 to 25 individuals, typically using caves for shelter. Had a hunter gatherer lifestyle.

  • Large amounts of meat in diet results of effective co-operative hunting of large prey animals (possibly as large as a mammoth)

  • Advances in culture accounted for by more sophisticated tools (Mousterian compared with Acheulean) likely to have had more sophisticated communication, ability to make shelters as well as clothes

  • Movement of females reduced genetic effect of interbreeding, may also have aided transmission of culture between groups

24. Explain the statement by Svante Paabo: ‘Those of us who live outside Africa carry a little Neanderthal DNA in us’.

DNA analysis has determined up to 4% of the DNA of Neanderthals is found in present-day humans who live outside Africa, providing evidence Neanderthals and sapiens bred after sapiens migrated out of Africa and into Europe where they met up with the Neanderthals. Those who live outside Africa have ‘scored’ a bit of Neanderthal DNA in their genome.

25. Describe the Denisovans, and account for:

  • differences in the DNA compared with Neanderthal DNA

  • the presence of Denisovan genes in present day populations of Papua New Guinea and Aboriginal Australians but not the populations of mainland Asia

Denisovans were an offshoot of Neanderthals who migrated east and ended up in isolation in Siberia

  • differences develop in DNA compared with that of Neanderthals from different selection pressures and lack of gene flow

  • interbreeding occurred with H sapiens, who migrated through the Denisovans had become extinct by the time the second wave of migrating H sapiens reached the area and remained to become present day Asians

26. Give reasons for the Neanderthals becoming an evolutionary dead end.

Neanderthals became extinct, so did not leave any present day descendants. They were cold adapted and may not have been able to tolerate the warm climate that followed the end of the ice age. This change may have also removed / reduced the food sources of Neanderthals, further reducing their chances of survival. Direct competition with the more sophisticated H sapiens may have seen Neanderthals outcompeted and eliminated.

27. In 2004, scientists excavating a cave site on the island of Flores in Indonesia found the remains of an extinct group of very small people who were alive until possibly 13 000 years ago. Views of the skulls are shown. A modern human skull is shown for comparison.

Based on features of the skull and the rest of the bones found with the skull, the remains have been placed in a separate species, Homo floreniensis. This species seems to be more closely related to Homo erectus than to Homo sapiens.

a. Describe one feature of the skull found in the cave that would show that the species it belonged to walked upright.

The foramen magnum would be located centrally at the base of the skull. Small nuchal crest for neck muscle attachment.

b. Without considering the overall size of the skull, the scientists concluded that the skull belonged to a hominin of the genus Homo. They also decided that the species Homo floresiensis more closely resembles Homo erectus than it resembles Homo sapiens. Apart from size, compare and contrast features of the two skulls, and the evolutionary trends of Homo erectus and Homo sapiens, that support the scientists’ conclusions.

The skull has more primitive features, usually associated with H erectus. The forehead is lower, making the size of the face compared with the cranium small. The cranium is also less domed / flatter than that on the H sapiens skull, indicating small brain volume. The H floresensis skull has more buttressing with large brow ridges and thicker zygomatic arches compared to that of H sapiens’ skull. It also has small sagittal crest compared to H sapien – which is absent. These features reduces the stress of chewing when the diet consists of a lot of tough plant material. H floresensis also has larger molars and a more robust jaw than H sapiens. The foramen magnum is centrally located, so H floresensis stood upright.

These features indicate that H floresensis was probably more like H erectus in its brain development and thus its cultural evolution should be similar e.g. tool use, communication

c. Studies of the inside of the skull show that Wernicke’s area of the brain was well developed.

i. Describe the function of Wernicke’s area of the brain.

Language communication

ii. Explain how Wernicke’s area of the brain would be an advantage to the species for the hunting of animals that were very large in comparison with Homo floresiensis.

If they could communicate with one another, hunting and kills could be planned and co-ordinated to minimise risks, and they would be to use group hunting tactics to capture larger prey.

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