Population Movements and Genetics - IELTS Reading Sample with Explanation

The IELTS Reading section contains three passages and forty questions. There are different types of questions found in each IELTS reading passage. This IELTS reading sample -Population Movements And Genetics is an IELTS Academic topic. The passage contains the following question types from IELTS Reading Question Types:

• Choose the correct heading.
• Complete the table

There are similar topics found in IELTS reading practice papers from which candidates can prepare.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

Section 1

Read the Passage to Answer the Following Questions

Population Movement and Genetics IELTS Reading Sample

1. Study of the origins and distribution of human populations used to be based on archaeological and fossil evidence. A number of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing. The best information on early population movements is now being obtained from the 'archaeology of the living body', the clues to be found in genetic material.
2. Recent work on the problem of when people first entered the Americas is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonisers of the New World’. But was there one major wave of migration across the Bering Strait into the Americas, or several? And when did this event, or events, take place? In recent years, new clues have come from research into genetics, including the distribution of genetic markers in modern Native Americans 1 2.
3. An important project, led by the biological anthropologist Robert Williams, focused on the variants (called Gm allotypes) of one particular protein -immunoglobulin G - found in the fluid portion of human blood. All proteins 'drift', or produce variants, over the generations, and members of an interbreeding human population will share a set of such variants. Thus, by comparing the Gm allotypes of two different populations (e.g. two Indian tribes), one can establish their genetic 'distance', which itself can be calibrated to give an indication of the length of time since these populations last interbred.
4. Williams and his colleagues sampled the blood of over 5,000 American Indians in western North America during a twenty-year period. They found that their Gm allotypes could be divided into two groups, one of which also corresponded to the genetic typing of Central and South American Indians. Other tests showed that the Inuit (or Eskimo) and Aleut3 formed a third group. From this evidence it was deduced that there had been three major waves of migration across the Bering Strait. The first, Paleo-indian, wave more than 15,000 years ago was ancestral to all Central and South American Indians. The second wave, about 14,000-12,000 years ago, brought Na-Dene hunters, ancestors of the Navajo and Apache (who only migrated south from Canada about 600 or 700 years ago). The third wave, perhaps 10,000 or 9,000 years ago, saw the migration from North-east Asia of groups ancestral to the modern Eskimo and Aleut.
5. How far does other research support these conclusions? Geneticist Douglas Wallace has studied mitochondrial DNA4 in blood samples from three widely separated Native American groups: Pima-Papago Indians in Arizona, Maya Indians on the Yucatán peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-indian) population.
6. There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages. The biological anthropologist Christy Turner is an expert in the analysis of changing physical characteristics in human teeth. He argues that tooth crowns and roots5 have a high genetic component, minimally affected by environmental and other factors. Studies carried out by Turner of many thousands of New and Old World specimens, both ancient and modern, suggest that the majority of prehistoric Americans are linked to Northern Asian populations by crown and root traits such as incisor shoveling (a scooping out on one or both surfaces of the tooth), single-rooted upper first premolars6 and triple-rooted lower first molars6.

According to Turner, this ties in with the idea of a single Paleo-indian migration out of North Asia, which he sets at before 14,000 years ago by calibrating rates of dental micro-evolution. Tooth analyses also suggest that there were two later migrations of Na-Denes and Eskimo-Aleut.

7. The linguist Joseph Greenberg has, since the 1950s, argued that all Native American languages belong to a single 'Amerind' family, except for Na-Dene and Eskimo-Aleut - a view that gives credence to the idea of three main migrations. Greenberg is in a minority among fellow linguists, most of whom favour the notion of a great many waves of migration to account for the more than 1,000 languages spoken at one time by American Indians. But there is no doubt that the new genetic and dental evidence provides strong backing for Greenberg's view. Dates given for the migrations should nevertheless be treated with caution, except where supported by hard archaeological evidence.

1. New World: the American continent, as opposed to the so-called Old World of Europe, Asia and Africa
2. modem Native American: an American descended from the groups that were native to America
3. Inuit and Aleut: two of the ethnic groups native to the northern regions of North America (i.e. northern Canada and Greenland)
4. DNA: the substance in which genetic information is stored
5. crown/root: parts of the tooth
6. incisor/premolar/molar: kinds of teeth

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

Section 2

Solution and Explanation

Questions 1-6: Choose the correct heading for section A-F from the list of headings below.

Write the correct number i - x accordingly.

1. The results of the research into blood-variants
2. Dental Evidence
3. Greenberg’s analysis of the dental and linguistic evidence
4. Developments in the methods used to study early population movements
5. Indian migration from Canada to the U.S.A.
6. Further genetic evidence relating to the three-wave theory
7. Long-standing questions about prehistoric migration to America
8. Conflicting views of the three-wave theory, based on non-genetic evidence
9. Questions about the causes of prehistoric migration to America
10. How analysis of blood variants measures the closeness of the relationship between different populations

1: Section A

Answer: heading iv

Supporting sentence: A number of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing

Keywords: techniques, objective footing.

Keyword location: Paragraph A; line 2

Explanation: The paragraph talks in brief about the developments made in the study of human movement and gives an introduction to the same.

Read More IELTS Reading Related Samples

2:Section B

Answer: heading vii

Supporting sentence: Recent work on the problem of when people first entered America is an example of the value of these new techniques

Keywords: America, new techniques

Keyword location: Paragraph B; line 1

Explanation: The new techniques developed to study human migration helped a lot in cracking the secret of the American migration in the ancient periods.

3:Section C

Answer: heading x

Supporting sentence: Thus, by comparing the Gm allotypes of two different populations (e.g. two Indian tribes), one can establish their genetic 'distance', which itself can be calibrated to give an indication of the length of time since these populations last interbred.

Keywords: allotypes, interbred, genetic

Keyword location: Paragraph C; line 4

Explanation: Because of human history, it is true that most of the human populations are similar to each other, and the new blood technique has helped measure how close two different populations are to each other.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

4:Section D

Answer: heading i

Supporting sentence: Williams and his colleagues sampled the blood of over 5,000 American Indians in western North America during twenty years. They found that their Gm allotypes could be divided into two groups, one of which also corresponded to the genetic typing of Central and South American Indians.

Keywords: American, Indian, North America

Keyword location: Paragraph D; line 1

Explanation: The paragraph talks about the research done by Williams regarding the blood samples and the data that has been found of the research.

5:Section E

Answer: heading vi

Supporting sentence: Geneticist Douglas Wallace has studied mitochondrial DNA4 in blood samples from three widely separated Native American groups: Pima-Papago Indians in Arizona, Maya Indians on the Yucatán peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-Indian) population.

Keywords: Douglas Wallace, ancestral

Keyword location: Paragraph E; line 1

Explanation: Further research done by Wallace is being talked about in this section, which explores deeply into the three-wave theory that had been previously talked about

6:Section F

Answer: heading ii

Supporting sentence: There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and languages

Keywords: Native American, languages, teeth

Keyword location: Paragraph F; line 1

Explanation: As teeth have minimal effect on the environment, they serve as great evidence to study human genetics and hence supplement the research on human movements.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

Questions 7-8: The discussion of Williams’s research indicates the periods at which early people are thought to have migrated along certain routes.

There are six routes, marked on the map below. (A-F)

Write the correct letter, A-F, and complete the table.

7:

Answer: route e

Supporting sentence: The first, Paleo-Indian, wave more than 15,000 years ago was ancestral to all Central and South American Indians

Keywords: Paleo-Indian, Central

Keyword location: Paragraph D; line 5

Explanation: Route e shows the route that could have possibly been taken by the paleo Indians, approximately 15000 years ago.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

8:

Answer: route d

Supporting sentence: The second wave, about 14,000-12,000 years ago, brought Na-Dene hunters, ancestors of the Navajo and Apache (who only migrated south from Canada about 600 or 700 years ago).

Keywords: second wave, Na-Dene

Keyword location: Paragraph D; line 6

Explanation: Route d was adopted by migrators approximately 12000 years ago, which brought Na-Dene hunters to the current American region.

Questions 9-12: Reading Passage refers to the three-wave theory of early migration to the Americas. It also suggests in which of these three waves the ancestors of various groups of modern native Americans first reached the continent.

Classify the groups named in the table below as originating from

Write the correct letter. A, B or C, in boxes 9-12.

9:

Answer: third wave

Supporting sentence: Other tests showed that the Inuit (or Eskimo) and Aleut formed the third group.

Keywords: Inuit, Aleut

Keyword location: Paragraph D; line 4

Explanation: The Inuit group of migrators was found to be a part of the third wave of human migrations along with the Aleut group.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

10:

Answer: second wave

Supporting sentence: The second wave, about 14,000-12,000 years ago, brought Na-Dene hunters, ancestors of the Navajo and Apache

Keywords: second wave, Navajo, and Apache

Keyword location: Paragraph D; line 6

Explanation: As talked about above, the Na-Dene hunters, which were ancestors of the Apache group, were part of the second wave of human migration.

11:

Answer: First wave

Supporting sentence: Pima-Papago Indians in Arizona, Maya Indians on the Yucatán peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-Indian) population.

Keywords: Pima-Papago Indians, Paleo-Indian

Keyword location: Paragraph E; line 2

Explanation: Pima-Papago Indians were found to be part of the ancestry of paleo Indians, which in turn meant that they were amongst the first wave of human migration 15000 years ago.

12:

Answer: the first wave

Supporting sentence: Pima-Papago Indians in Arizona, Maya Indians on the Yucatán peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams's work, all three groups appear to be descended from the same ancestral (Paleo-Indian) population.

Keywords: Pima-Papago Indians, Paleo-Indian

Keyword location: Paragraph E; line 2

Explanation: Just as Pima-Papago, Ticuna Indians were also ancestors to paleo Indians.

Check:  Get 10 Free Sample Papers

Check: Register for IELTS Coaching - Join for Free Trial Class Now

Question 13: Choose the correct letter, A, B, C, or D.

Christy Turner’s research involved the examination of -

A: teeth from both prehistoric and modern Americans and Asians.
B: thousands of people who live in either the New or the Old World.
C: dental specimens from the majority of prehistoric Americans.
D: the eating habits of American and Asian populations.

Answer: A

Supporting sentence: Studies carried out by Turner of many thousands of New and Old World specimens, both ancient and modern, suggest that the majority of prehistoric Americans are linked to Northern Asian populations

Keywords: Turner, specimens

Keyword location: Paragraph F; line 4

Explanation: Teeth are important evidence as they hardly get affected by the environment, and research done on dental evidence by turner has helped to establish that prehistoric Americans are related to north Asian people.