MODEL ANSWERS Date: 13.05.2013 AR-7926 Time

MODEL ANSWERS
Date: 13.05.2013
AR-7926
Time: 2.00 PM – 5.00 PM
B.A./B.Sc. (Hons.) (Inte.) Fourth Semester
Examination- 2013
Anthropology
(Paper-I)
Human Evolution
Maximum Marks: 45
Section- A
Note- This section contains ten objective type questions. Each question carries 1.5
marks.
Q1)
Objective type Questions:
10 x 1.5= 15
(i)
Who gave the theory of Pangenesis?
a. Charles Darwin; b. A. Weismann; c. Washburn; d. None of these
Answer: a. Charles Darwin
(ii)
Who was ‘Lucy’?
a. Australopithecus africanus; b. Homo habilis; c. Australopithecus aferensis;
d. None of the above.
Answer: c. Australopithecus aferensis
(iii) Great apes are mainly found in;
a. Asia; b. Europe; c. Africa; d. America
Answer: c. Africa
(iv) Sagittal crest is observed in:
a. Chimpanzee; b. Gorilla; c. Orangutan; d. Langur
Answer: b. Gorilla
(v)
Which one is the example of palaeontological evidence of organic evolution?
a. Archaeopteryx; b. Bird; c. Reptiles; d. None of the above
Answer: a. Archaeopteryx
(vi) Who discovered Homo-erectus javanensis?
a. Lewis; b. Leaky; c. Raymond Dart; d. Eugene Dubois
Answer: d. Eugene Dubois
(vii) New world monkey are also known as:
a. Platyrrhine; b. Catarrhini; c. Both a & b; d. None
Answer: a. Platyrrhine
(viii) In which year Australopithecus boisei was discovered?
a. 1973; b. 1959; 1924; d. None
Answer: b. 1959
(ix)
Who discover fossil remains of Ramapithecus from Siwalik hills?
a. M.L. Lartet; b. Raymond Dart; c. G.E. Lewis; d. None of the above
Answer: c. G.E. Lewis
(x)
Who discover “Taung baby”?
a. Raymond Dart; b. Eugene Dubois; c. Anderson & Zdansky; d. Leaky
Answer: a. Raymond Dart
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Section B
(Long Answer type question)
04 x 7.5= 30
Q2. Answer: Sinanthropus pekinensis:
Specimen: A reconstructed skull on the basis of a dozen incomplete skulls, mandibles
and 147 teeth. The reconstruction was done by F. Weidenreich, and is known
from his report: The skull of “Sinanthropus pekinensis”. The basis for
reconstruction was the most complete skull of a lightly built female. The mind
portion of the face is sheer guesswork.
Discoverer: The first calotte (skull III) was discovered by W.C. Pei in 1929.
Site: Lower cave at Zhoukoudian, 30 miles southwest of Bejing (erstwhile, Peking),
China.
Geological Age: Middle Pleistocene, about 300,000 year’s age.
Physical features: (Cast of reconstructed skull).
1. The contour is long and oval-narrow in front and wider behind.
2. Cranial Sutures are not traceable (fused).
3. The supraorbital torus is heavy and projecting.
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Phylogenetic position and affinity:
The middle Pleistocene hominid finds from the limestone cave of Zhoukoudian,
near Beijing, China was attributed the designated “Sinanthropus pekinensis” by Dr.
Davidson Black. Dr. F. Weidenreich made a detail comparative study of the skull with
the Java specimen (Pithecanthropus). From that comparative study it was inferred that
both the finds belong to the same genus, Pithecanthropus. Later, by 1940, both
Sinanthropus and Pithecanthropus materials were included in the genus Homo and in
1950 in the species H. erectus. They are distinguished at the subspecific level.
Systematic position
Order:
Primates
Suborder
Anthropoidea
Superfamily
Hominidea
Family:
Hominidae
Genus:
Homo
Species:
H. erectus
Subspecies:
H. e. pekinensis
Trinomial name
Homo erectus pekinensis
(Black, 1927)
Synonyms
Sinanthropus pekinensis
Q3. Choukoutine man:
Specimen: Late in 1929, after years of digging, the paleontologists at the site
finally reached the layer that they were searching for, that held the remains of forty
ancient human ancestors. The remains were found in a chasm uncovered after
breaching a thick layer of black clay. A partial skull, consisting of most of the
braincase but almost none of the face that had been found at Zhoukoudian.
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Discoverer: On December 2nd by W. C. Pei, the young Chinese scientist in
charge of excavation at the site.
Site: Lower cave at Zhoukoudian, 30 miles southwest of Bejing (erstwhile, Peking),
China.
Geological Age: Middle Pleistocene, about 300,000 year’s age.
Physical features: (Cast of reconstructed skull).
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Phylogenetic position and affinity:
The middle Pleistocene hominid finds from the limestone cave of Zhoukoudian,
near Beijing, China was attributed the designated “Sinanthropus pekinensis” by Dr.
Davidson Black. Dr. F. Weidenreich made a detail comparative study of the skull with
the Java specimen (Pithecanthropus). From that comparative study it was inferred that
both the finds belong to the same genus, Pithecanthropus. Later, by 1940, both
Sinanthropus and Pithecanthropus materials were included in the genus Homo and in
1950 in the species H. erectus. They are distinguished at the subspecific level.
Systematic position
Order:
Primates
Suborder
Anthropoidea
Superfamily
Hominidea
Family:
Hominidae
Genus:
Homo
Species:
H. erectus
Subspecies:
H. e. pekinensis
Trinomial name
Homo erectus erectus
Synonyms
Choukoutine man
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Q4. Java man:
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7
Q5. Classification of Order Primate by Simpson (1945)
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Q6. Answer: Lucy
Specimen: The first A. afarensis skeleton was discovered on November 24, 1974 near
Hadar in Ethiopia by Tom Gray in the company of Donald Johanson, as part of a team
involving Maurice
Taieb, Yves
Coppens and Tim
White in
the Middle
Awash of Ethiopia's Afar Depression. The most famous fossil is the partial skeleton
named Lucy (3.2 million years old) found by Donald Johanson and colleagues, who, in
celebration of their find, repeatedly played the Beatles song Lucy in the Sky with
Diamonds. Australopithecus afarensis is an extinct hominid that lived between 3.9 and
2.9 million years ago. A. afarensis was slenderly built, like the younger Australopithecus
africanus.
It
is
thought
that A.
afarensis was
more
closely related
to
the
genusHomo (which includes the modern human species Homo sapiens), whether as a
direct ancestor or a close relative of an unknown ancestor, than any other known primate
from the same time.
Discovery: Australopithecus afarensis fossils have only been discovered within northern
Africa. Despite Laetoli being the type locality for A. afarensis, the most extensive
remains assigned to the species are found in Hadar, Afar Region of Ethiopia, including
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the above-mentioned "Lucy" partial skeleton and the "First Family" found at the AL
333 locality. Other localities bearing A. afarensis remains include Omo, Maka, Fejej and
Belohdelie in Ethiopia, and Koobi Fora and Lothagam in Kenya.
Characteristic Features:
A; Skull and brain size
1. Compared to the modern and extinct great apes, A. afarensis has reduced canines and
molars, although they are still relatively larger than in modern humans.
2. A. afarensis also has a relatively smallbrain size (~380–430 cm3) and a prognathic face
(i.e. a face with forward projecting jaws).
3. The image of a bipedal hominid with a small brain and primitive face was quite a
revelation to the paleoanthropological world at the time. This was due to the earlier belief
that an increase in brain size was the first major hominin adaptive shift.
B: Skeletal morphology and locomotion
1. Morphology of scapula appears to be ape-like and very different from modern humans.
2. The curvature of the finger and toe bones (phalanges) approaches that of modern-day
apes, and is suggestive of their ability to efficiently grasp branches and climb.
3. The loss of an abductable great toe and therefore the ability to grasp with the foot (a
feature of all other primates) suggests A. afarensis was no longer adapted to climbing.
4. A number of traits in the A. afarensis skeleton strongly reflect bipedalism, the pelvis is
far more human-like than ape-like.
5. The iliac blades are short and wide, the sacrum is wide and positioned directly behind
the hip joint, and evidence of a strong attachment for the knee extensors is clear.
6. The pelvis is not wholly human-like (being markedly wide, or flared, with laterally
orientated iliac blades), these features point to a structure that can be considered radically
remodeled to accommodate a significant degree of bipedalism in the animals' locomotor
repertoire.
7.
The femur also angles in toward the knee from the hip.
8.
The feet also feature adducted big toes, making it difficult if not impossible to
grasp branches with the hindlimbs.
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9.
The loss of a grasping hindlimb also increases the risk of an infant being dropped
or falling, as primates typically hold onto their mothers while the mother goes about her
daily business.
10.
Bones of the foot (such as the calcaneus) also indicate bipedality.
Phylogenetic position: The discovery of a 3.2 million
year-old bone in
Hadar, Ethiopia at the AL 333 site was announced In February 2011. The foot bone
shows that the species had arches in its feet, which confirmed that the species walked
upright for the majority of the time. The foot bone is one of 49 new bones discovered,
and indicates that A. afarensis is "a lot more human-like than we had ever supposed
before", according to the lead scientist on the study.
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Primates
Family:
Hominidae
Subfamily:
Homininae
Genus:
Australopithecus
Species:
A. afarensis
Binomial name
Australopithecus afarensis
(Johanson & White, 1978)
Q7. Answer:
Organic Evolution: It Is The Process Of Gradual Change Of An Organism From
Simpler To Complex Form. Organic, Or Biological, Evolution Is The Modification Of
Living Organisms During Their Descent, Generation By Generation, From Common
Ancestors. The term evolution is derived from Latin word evolve which means unfolding
or unrolling which implies the process of gradual and orderly change from one condition
to another through succession or a series of changing events. By organic evolution it is
understood that the gradual and orderly changes are taking place in all life forms on the
earth's crust, since the origin of first life. According to the doctrine of organic evolution
as propounded by Charles Darwin the plants and animals of present day form are the
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descendants of the plants and animals of the past and are the progenitors of plants and
animals of the future.
Eevidences of organic evolution
The theories which we have discussed are imaginary. There is no practical proof
for them. The various animals which we are seeing to-day were gradually evolved from
simple past lived organisms. It is not possible for anybody to observe a single change,
because our life span is too short. Hence scientists collected evidences from
different branches of biology. They are,
1. Morphological and anatomical evidences.
2. Embryological evidences
3. Paleontological evidences.
4. Physiological evidences.
5. Zoo geographical evidences.
a. Morphological and anatomical evidences
1. Homologous organs
The organs which have common origin and structure are called homologous
organs. The homologous organs may differ in function and form (shape).
a. Homologous organsExample - If we observe the fore limb of a frog, wing of a bird, paddle of a whale and
hand of a man, all of them have same origin and same structure. Each of the organs has
same bones, same blood vessels and same nerves. Because the above animals are living
in different habitats and the organs have to perform different functions. In frog, the
homologous organs (fore limbs} perform leaping movement. In birds, the homologous
organs (wings) perform flying movement. In whale, the homologous organs (paddles)
perform swimming movement. In man, the homologous organs (hands) perform holding
of objects.
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Analogous organs
The organs which have common form and function are called analogous organs. But they
must differ in origin and structure.
The wings of insect, bird and bat. In both the wings perform flying. But the wing of
insect is derived from ectoderm and it is supported by chitinous nervures. Whereas the
wing of bird is derived from mesoderm and it is supported by bones.
Vestigeal organs
The organs which are non functional and reduced in an organism are called vestigial
organs. But these organs were well developed and performed functions in ancestors. The
organs become functionless when the animals enter into new habitat or when their
function is taken up by another organ or when the habits are changed. Presence of
vestigial organs is the most convincing evidence in favour of organic evolution. Eg.,
Wisdom teeth, body hair etc.
Embryological principles
Von Baer proposed these principles by studying the embryology of fish, frog, tortoise,
pigeon, chimpanzee and man. The early embryos of above animals resemble with each
other closely. That it is impossible to separate if the embryos were mixed. But the
embryos differ in the final stages clue to the formation of specialized characters. The
similarity of early embryos tells that the above animals have common ancestors.
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1. Fossils
Study of the past lived organisms which are not now on the globe or fossils is called
paleontology. Normally hard parts like spicules, setae, chitinous exoskeleton, shells,
spiny exoskeleton, scales, bones, feathers, teeth and hair of past lived organisms were
preserved as fossils.
2. Fossilisation
It is the process of formation of fossils of past lived organisms. Normally an animal
becomes fossil due to sudden environmental change. Majority of the fossils are formed
by petrifaction. It is the process of replacement of organic matter by minerals like sand,
lime, iron oxides etc.
3. Fossils collection
Fossils are exposed due to natural erosion of the soil or by excavation (digging of the
soil). In india fossil collection and observation are being conducted by birbalsahni
institute of palaeobotany, Lucknow. It observed three fossil parks in India.
a. Deccan plateau of Mandla District, M.P
The paleontologists collected 50 million years old fossil forest trees.
b. Rajmahal hills, Bihar:
Scientists collected 100 million years old fossils.
c. Coal mines of Orissa:
Scientists collected 260 million years old fossils.
4. Fossils-types
The fossils are four types. They are unaltered, altered, moulds and coprolite fossils.
5. Geological time scale – observations
Archaeopteryx: this missing link was collected from jurassic period. The archaeopteryx
contains the structures of both reptiles and aves.
Evolution-physiological evidences
Study of the functional aspects of the organism is called physiology. The organs and
organ systems are similar in the closely related animals. The functional aspect of closely
related animals is also same. The physiological evidences are studied in three headings;
they are:
1. Fundamental unity of life,
2. Biochemical similarities between groups and
3. Biochemical recapitulations.
5. Zoo geographical evidece of evolution
The study of the distribution of animals on the globe is called zoo geography. The
different kinds of animals living in a particular area form the fauna. The geographical
distribution of animals provides a good evidence for organic evolution.
a. Fauna of Africa and Madagascar
For example the fauna of Africa belongs to Ethiopian region differs from the fauna of
Madagascar even though both the regions are present in subtropics.
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b. Fauna of Australia and South America –
The fauna of South America located d inneotropical region consists of bears, llamas,
sloths, armadillos etc.
c. Fauna of poles
The south and north poles consist of same ecological conditions. The South Pole consists
of penguins, where as the north pole consists of polar bears. This difference is mainly due
to adaptability.
d. Fauna of Northeren hemisphere
The continents, North America and Eurasia of northern hemisphere consist of same
fauna.
Q8. Answer:
Australopithes africanus: An Australian anatomist at the University of the
Witwatersrand, Johannesburg, South Africa, named Raymond Dart, discovered the first
australopithecine in November 1924 and published his interpretation of it in the
journal Nature in February 1925. The fossil was that of an immature apelike individual
and was found at a lime quarry at Taung, southwest of Johannesburg. The fossil existed
of the face, part of the cranium, the complete lower jaw and a brain endocast, formed
when sand inside the skull hardened to rock, recording the shape of the brain.
Australopithecus africanus appeared to be apelike in having a protruding face and
small brain, but had distinctly unapelike dentition, including small canines and large, flat
molars. A bipedal posture was again indicated by the central position of the foramen
magnum, and by the anatomy of the spine, pelvis, and femur.
Dating these South African australopithecines has been a difficult task, because
their cave context is not appropriate for radiometric dating. Ranges have been tentatively
suggested for 3.5 to 2.5 million years for the gracile australopithecines and 2.0 to 1.0
million years for the robust species.
Australopithecus aferensis: The earliest known hominine for which sufficient
diagnostic anatomical evidence was available was Australopithecus afarensis, fossils of
which have been found in Ethiopia, Tanzania, and Kenya, and most of which date
between 2.9 and 3.9 million years. New finds of fossils as old or older than A.
afarensis have been made in Ethiopia, Kenya, and Chad. These speciments, which are
sufficiently different from A. afarensis to have been named a new species, include the
following:
Ardipithecus
ramidus from
Ethiopia,
dated
at
4.4
million
years; Australopithecus anamensis from Kenya, with an age range of 4.2 to 3.9 million
years; and Australopithecus bahrelghazali from Chad, with an age estimate of 3 to 3.5
million years.
The first afarensis fossils were found in the mid 1970s. Their initial interpretation
was controversial and remains so today, albeit to a lesser degree. While many
anthropologists accept that the multitude of fossil specimens that have been attributed
to afarensis do indeed represent a single, sexually dimorphic species, others believe that
the fossils belong to two, and perhaps more, species. For a long time afarensis was
assumed to have represented the founding species of the hominine clade and the ancestor
of all later species.
The most spectacular of these finds was the partial skeleton named "Lucy"; in
addition, remains of 13 individuals were found at a single site and were subsequently
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dubbed the First Family. It was clear from the start that some of the homninines were
small while others were large.
Johanson and White described A. afarensis as being much more primitive than
other known hominies, with a strongly apelike appearance above the neck and a stronly
humanlike form below the neck; as having extreme sexual dimorphism in body size
(males larger than females); and as being ancestral to all later hominines.
This table shows the main morphological differences between the two main
members of the so-called "gracile" Australopithecine family; Australopithecus
afarensis and Australopithecus africanus.
Variables
Height
Weight
Cranial Volume
Known Date
Distribution
Physique
A. afarensis
1.0 - 1.5 metres
30 - 70 kg
400 - 500 cc
4.0 - 2.5 million years ago
Eastern Africa
Light build; some ape-like
features
Skull form
Low,
flat
forehead;
projecting face; prominent
brow ridges
Relatively large incisors
and canines; gap between
upper incisors and canines;
moderate-sized molars
Marked to moderate
Jaws/Teeth
Sexual Dimorphism
A. africanus
1.1 - 1.4 metres
30 - 60 kg
400 - 500 cc
3.0 - 2.5 million years ago
Southern Africa
Light
build;
probably
relatively long arms; more
"human" features
Higher forehead; shorter
face; brow ridges less
prominent
Small incisor-like canines;
no gap between upper
incisors and canines; larger
molars
Probably
less
than A.
afarensis
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