Human Evolution

Origin and evolution of man and apes: 

1. Chromosomal similarities:  
   (i) The banding pattern of chromosome no. 3 and 6 of human and chimpanzee is 100% similar.  
   (ii) Number of chromosomes is approx. same in humans (46) and apes (48). 
   (iii) DNA content and DNA matching are the same in both. This similarity is more than 99% with chimpanzees, 94% with Gibbon, and 88% with Rhesus monkey.
2. The skull of the baby chimpanzee is more like an adult human skull than an adult chimpanzee skull. 
3. The composition of Hb is the same in both. Only one amino acid is different in humans and gorillas.
4. The blood group of AB series is present in both and plasma protein is also the same.
5. The menstruation cycle is present in females of both.
6. The tail is absent in both and has grasping hands. 
   

   	Apes	Human
   1.	Semi-erect posture	Complete erect posture with bipedal locomotion
   2.	The thick growth of hair on the whole body	The thick growth of hair only on certain parts of the body.
   3.	Less cranial capacity (450 cc) and less intelligence.	More cranial capacity (1300-1600 cc) and more intelligence.
   4.	Forelimbs longer than hind limbs	Forelimbs shorter than hind limbs
   5.	'U' shaped jaw & chin absent	Semicircular jaw and chin present
   6.	Thumb is parallel to plam	Thumb is opposable.

Human Evolution:  

1. Ape Fossils:

About 15 mya, primates called Dryopithecus and Ramapithecus were existing. They were hairy and walked like gorillas and chimpanzees. 

(i) Proconsul/ Dryopithecus:

•  It is considered a common ancestor of man and apes.
• Dryopithecus is considered as direct ancestors of modern-day apes.  
• They had semi-erect posture, thick hair, U-shaped jaws, larger and sharper teeth and were vegetarian.  
• They walked on four legs and their forelimbs were longer than hind limbs. - They were forest dwellers and spent most of their time on the trees.  

(ii) Ramapithecus and Shivapithecus: Fossils discovered from Shivalik hills in India. 

(iii) Kenyapithecus:

• Fossils were discovered in Kenya.
• They are considered ancestors of human, similar in characteristics to Dryopithecus, but spent most of the time on the land. 
• Ramapithecus was more man-like while Dryopithecus was more ape-like.  

2. Ape man fossils:

• Australopithecus Prof. Raymond Dart discovered a fossil of the skull of a 5-6 years old baby from the Pliocene rocks of the Tuang region (S. Africa) and named it Tuang baby. Later he renamed it A. africanus (African apeman).  
• 2 mya, Australopithecines probably lived in East African grasslands.
• Evidence shows they hunted with stone weapons but essentially ate fruit.
• It is also considered a connecting link between apes and man.  

(i) Ape-like characters:  

• The less cranial capacity (600 c.c.)  
• The thick growth of hair  
• U-shaped jaw (prognathous face)  
• Larger and sharper teeth 

(ii) Man-like characters:   

• Complete erect posture and Bipedal locomotion (the first man who stood erect)  
• Forelimbs shorter than hind limbs  
• Vertebral column with distinct lumber curve 

3. Prehistoric Man: 

A number of other species of Homo appeared and became extinct from time to time on the evolutionary sense before the origin of Homo sapiens. These extinct species are called prehistoric species of man. 

4. Homo habilis: 

• The first human-like being  
• The first man who made tools of stones for hunting animals hence called as first tool maker man or Handy man. 
• They probably did not eat meat. 
• The brain capacities were between 650-800cc. 
• Its fossils were discovered by Dr. Leakey from 2 million years old rocks in Africa.
• They lived in caves. 
  

5. Homo erectus:  

• They existed about 1.5 million years ago. 
• They had a large brain with a cranial capacity of around 900 cc.
• They were cave dwellers and probably ate meat.
• Many subspecies are discovered of Homo erectus as given below. 

i) Java man (Homo erectus erectus/ Pithecanthropus erectus): 

• Its fossils were discovered in java in 1891. 
• The first man who used fire for huntinA)g, protection, and cooking.
• They used tools of bones and stones. 
• Their cranial capacity was 800-1000cc (avg.900 cc) 
• They were omnivorous and cannibalism have also found. 
   

ii) Peking man (Homo erectus pekinensis/ Sinanthropus erectus): 

• W.C. Pei discovered the fossils from china. 
• They used fire for cooking meat and for protection  
• They used sharp chisel-shaped tools of stones/bones for cutting and killing animals 
• Their cranial capacity was 850-1300cc (avg. 1050cc)  
• They were omnivorous and cannibalism has also found.  

iii) Heidelberg man:  

• Its fossil was recovered in form of a lower jaw from Heidelberg in Germany.  
• It is believed that this man evolved as a branch from the main line of evolution and got extinct after some time.  

6. Homo sapiens: 

•  Many subspecies are discovered of Homo sapiens as given below:  

i) Neanderthal man (Homo sapiens neanderthalensis):  

• They lived near east and central Asia between 1,00,000 - 40,000 years back, fossil was discovered by Fulhrott in the Neanderthal valley of Germany.  
• They had a brain size of 1400cc (same as a modern man).  
• They used hides (skin of animals) to protect their body.  
• They buried their dead and probably believed in the immortality of soul.
• They lived in huts and omnivorous by nature.  
• Development of speech centre and language started.  
  
  

ii) Cromagnon man (Homo sapiens fossilis):  

•  Origin and evolution 50,000 to 10,000 years ago. 
• Fossils were discovered by Mac Gregor from Cromagnon rocks of france. 
• They had a cranial capacity of 1650 c.c. (maximum) 
• They lived in caves and were omnivorous by nature. 
• They had a larger forehead and well-developed chin.
• Semi-circular jaw and orthognathous face.
• Speech and language centre were well developed in them.
• They wore clothes of animal skin. 
• This man was a hunter and used domesticated dogs in hunting, hence domestication was started by this man. 
• They also painted beautiful paintings on cave walls. Pre-historic cave art developed about 18,000 years ago. Such cave paintings by a prehistoric man can be seen at the Bhimbetka rock shelter in the Raisen district of Madhya Pradesh. 

iii) Modern man (Homo sapiens sapiens):  

• During ice age between 75,000-10,000 years ago modern Homo sapiens arose.  
• It arose in Africa and moved across continents and developed into distinct races (Caucasoid, Negroid, Mongoloid, and Australoid).  
• This is the man of today having a brain capacity of 1300 - 1600 c.c (avg. 1450cc).  
• This man has a well-developed chin, well-developed speech center, a smaller forehead, and reduced body hair.  
• Semi-circular jaw and orthognathous face. - It is omnivorous by nature. 
• Agriculture was also started by this man. Agriculture came around 10,000 years back and human settlements started.