Unit 11. Human evolution

Lexis: Evolutionary biology / Anthropology / Paleontology / Genetics / Demography Listening. 5 texts.

Text a. Human evolution and palaeobotany

Exercise 1. Listen to the text (Script 29) which offers a new explanation of why bipedalism evolved in apes. How do the new findings contradict the established theory?

plausible – правдоподобный, вероятный sediment – нанос, осадочные отложения detritus – детрит, скопление обломков породы

Exercise 2. Listen to the text again. Using information from the text prove the following statements:

1. Transformation of Africa’s landscape was the driving force of human evolution.

2. The ratio of carbon isotopes contained in plants allows to date their origin.

3. Grasslands were present in East Africa before upright posture evolved.

Text b. Human evolution

Exercise 3. Put the following Australopithecus and Hominid species in the chronological order of their origin and existence by matching the species (a to g) with the dates (1 to 7)¹:

1) 3-1 mln years ago	a) Neanderthals
2) 2,4-1,9 mln years ago	b) Homo sapiens
3) 2-1.6 mln years ago	c) Homo rudolfensis
4) 1,8-1,3 mln years ago	d) Australopithecus
5) 1,5-0,4 mln years ago	e) Homo erectus
6) 0,4 - 0,3 mln years ago	f) Homo habilis
7) 0,2-0,1 mln years ago	g) Homo ergaster

to predate – предшествовать, датироваться более ранним числом frontal lobe – лобная доля головного мозга

Exercise 4. Listen to the text (Script 30) which describes a recently discovered species of the genus Australopithecus. How does this discovery amend the chronology of Homo evolution?

Exercise 5. Listen to the text again. What information is presented in the text on:

- the transition from australopithecine to the Hominids,

- the recently discovered fossils of the new species Australopithecus sediba,

- Australopithecus sediba’s anatomy and its implications,

- the relation of Australopithecus sediba to Homo,

- the emergence of Homo and evolutionary transformations,

- the dating and classification of Australopithecus sediba,

- the amended chronology of the transition from australopithecines to Hominids.

Text c. Evolution of skin colour

Exercise 6. Answer the questions:

1. How has the colour of the human skin changed over the course of evolution?

2. What was the driving force behind such changes?

3. What is albinism?

basal-cell carcinoma – базалиома, базально-клеточный рак squamous-cell carcinoma – плоскоклеточный рак expendable – ненужный, одноразового применения prejudice – предубеждение to ostracise – подвергать остракизму, изгонять из общества, отвергать forebear – предок, прародитель, предшественник

Exercise 7. Listen to the text (Script 31) to check your answers in Exercise 6. What major hypotheses explain the reasons why humans evolved different skin colours?

Exercise 8. Listen to the text again and explain what the following figures refer to in the text:

25 1980 512 26

125 20 thousandfold 10%

Exercise 9. Using information from the text prove the following statements:

1. As most types of skin cancer generally affect older people, cancer cannot be considered the driving force behind the evolution of skin colour.

2. Albinos demonstrate much higher risk of skin cancer.

3. Relatively harmless age-associated diseases - basal-cell and squamous-cell carcinomas - become much more virulent in albinos.

4. There is no agreement in the scientific world on why humans became naked apes.