Human evolution Session 25

Question 1

what is a traditional fossil ?

Answer 1

• It is a fossil that has characteristics of two different groups

Question 2

What is the study of Biogeography refered to ?

Answer 2

• The study of the distribution of plants and animals in different places

Question 3

What are classified as Anatomical evidence ?

Answer 3

• If there is the presence of Homologous structures , vestigial structures , and similar embryological development.

Question 4

What are homologous structures ?

Answer 4

• They are structures that are anatomically similar because they are inherited from a common ancestors

Question 5

What are Analogous structures ?

Answer 5

• They are structures that serve the same function but are not contracted similarly nor do they share a common ancestry

Question 6

What are some examples of vertebrate forelimbs containing the same set of bones organized in similar ways , but have different functions ?

Answer 6

• Birds and bats using them for flight
• Whales and seals using them for swimming
• horses using them for running

Question 7

What are vestigial structures ?

Answer 7

• They are structures that are fully developed in one organism but a re reduced and may have no function in others

For example ; humans have a tailbone but no tail

Question 8

Since vertebrates have similar embryological development , what are some things that all vertebrates have during development but may develop into different things ? State one example as well

Answer 8

• A tail and paired pharyngeal pouches
• In fish and amphibian larvae , the pouches develop into functioning gills
• In humans the pouches become cavity of the middle ear , auditory tube , tonsils , thymus and parathyroid glands

Question 9

What is the correct order of evolution and classification of humans ?

Answer 9

1. Domain Eukarya : membrane bound nucleus
2. Kingdom Animalia : multicellular , motile and heterotrophic
3. Phylum Chordata : dorsal tubular nerve cord , notochord , pharyngeal pouches
4. Class Mamalia : Vertebrates with hair , mammary glands
5. Order primates : Well developed brain , adapted to live in trees
6. Family Hominidae : Adapted to upright stance and bipedal locomotion
7. Genus Homo : Most developed brain , made and used tools
8. Species Homo sapiens : Modern humans

Question 10

According to rRNA sequence , what are the three domains of life, characterize each one ?

Answer 10

• Bacteria : Cells do not contain a nucleus
• Archaea : cells do not contain a nucleus , they have a different cell wall from bacteria
• Eukarya : cells do contain a nucleus

Question 11

What are the two different groups of primates and list examples for each group ?

Answer 11

• Prosimians : lemurs, tarsiers and lorises
• Anthropoids : monkeys , apes and humans

Question 12

What are some features of the primate ?

Answer 12

• Mobile limbs
• Grasping hands
• Flattened face
• binocular vision
• large brain
• reduced rate of reproduction

Question 13

What is known as the closest cousin to humans?

Answer 13

• Chimpanzee

Question 14

what are classified under the Hominid?

Answer 14

• Big apes(gorillas and orangutans) , chimpanzees , humans and the closest extinct relatives of humans

Question 15

What are classified under Hominine ?

Answer 15

• Only the gorillas , chimpanzees , humans and their closest extinct relatives

Question 16

What are classified under Hominin ?

Answer 16

• All members of the genus Homo and their extinct close relatives

Question 17

How big is a chimpanzees brain in comparison to a humans?

Answer 17

• Chimpanzees have a brain size about a third that of humans

Question 18

What are some unique hominid anatomical features ?

Answer 18

• Bipedal posture ( walking on two feet ) , the shape of the face and brain size

Question 19

When was the fossil Sahelanthropus tchandesis dated and where was it found ?

Answer 19

• 7 MYA , in chad , in central africa (2001)

Question 20

When was the fossil orrorin tugenensis dated and where was it found ?

Answer 20

• 6 MYA and Eastern Africa

Question 21

What were the two different species of ardipithecines found and when were they dated to be ?

Answer 21

• Ardipithecus kadabba dated 5.6 MYA
• Ardipithecus ramidus dated 4.4 MYA