Origin and Evolution of Man

The scanned notes state that anthropologists have made extensive studies to determine the origin and evolution of modern man, identified there as Homo sapiens sapiens.

According to the source, fragmentary fossil records suggest that humans arose in the plains of Asia, Africa and Europe from non-human or ape-like forms that lived about 20–24 million years ago. The source also assumes that modern man might have evolved from some primitive eutherian mammals during the Cretaceous period.

Evolutionary Trends in Humans

The source records the following human evolutionary changes:

• Bipedal locomotion and freeing of forelimbs from the ground.
• Loss of opposability of the great toes.
• Erect posture through development of the lumbar curve.
• Increase in the size and complexity of the brain.
• Reduction in the size of eyebrow ridges and in the size of canine and incisor teeth.
• Development of the chin.

Evolutionary Time Scale

The notes state that humans and modern apes had a common ancestor known as hominids, and presume that hominids existed about 24 million years ago. The source then gives the following divergence sequence:

Ancient Human Fossils

Page 2 identifies the fossils of Ramapithecus, Sivapithecus and Australopithecus as ancient human fossils.

The notes assume that these forms originated from a common ancestor associated with the origin of both apes and man, written in the source as Dryopithecus or Proconsul (Hominoid).

1. Ramapithecus

• It is considered in the source as a direct ancestor of man.
• The first record was found in the mid-1930s in the Northern Siwalik Hills of Asia.
• The notes state that Ramapithecus may have lived in Nepal about 11 million years ago.
• Teeth of such an ape are stated to have been found in south-western Nepal near the Dang Valley.
• The source describes a curved jaw with an arched palate.

2. Australopithecus

• It is described as the first human-like form.
• The notes state that it existed about 1–2.5 million years ago in the dry land of South Africa.
• The skull of African Australopithecus is described as resembling the skull of a human child and also that of a chimpanzee.
• Brain capacity was about 600 cc.
• They walked upright and showed more similarity to man.
• They probably weighed about 40–50 kg and were about 4–5 ft tall.

Modern Human Ancestors

The source states that the earliest ancestors belonging to the genus Homo are considered modern human ancestors. It recognizes several species from fossil records, including those described below.

I. Homo habilis

• It existed about 2 million years ago.
• Its fossils were recorded from East Africa.
• It was about 4.5 ft tall and weighed about 40–50 kg.
• It lived in open grassy land and was omnivorous.
• Cranial capacity was about 700 cc.
• It used tools for hunting and defence.

II. Homo erectus

The source states that the earliest fossils existed about 1.7 million years ago. It also mentions similar fossils recorded from Java and Peking and treats them as belonging to the same species, Homo erectus.

a. Java Man

• Fossils were recovered by Dubois in 1891 from Eastern Java.
• The source states that it existed about 50,000 years ago.
• Cranial capacity was about 900 cc.
• It was more than 5 ft tall and weighed nearly 70 kg.
• A prominent chin was absent, while eyebrow ridges were present over the eyes.
• The notes state that they might have constructed and used tools and also learned to light fire.

b. Peking Man

• Its fossils were recovered by W. C. Pei (1924) from caves near Peking in China.
• It was described as very similar to Java man.

III. Neanderthal Man

• Its fossils were found in the Neanderthal Valley of Germany.
• It resembled modern man and was relatively short, stocky and heavily built, about 5 ft tall.
• Cranial capacity was almost as large as that of modern man, about 1450 cc.
• The source states that its brain was almost as large as that of modern man.
• They were capable of communicating with each other and had a primitive type of social life, division of labour, religion and culture.
• They made tools for hunting and defence.
• They used animal hides (skin) for clothing.
• They made use of fire.
• They developed a tradition of burying dead bodies with ceremonies.

IV. Cro-Magnon Man

The source states that fossils of Cro-Magnon were first discovered in rock at Cro-Magnon in France in 1968 by Mac Gregor. It describes Cro-Magnon as modern man called Homo sapiens and states that it evolved about 10,000–50,000 years ago.

• They resembled modern man in size and appearance.
• Cranial capacity was about 1600 cc.
• They were about 5 ft tall.
• The forehead was broad and raised, the nose narrow and the chin prominent.
• They were progressive and experts in making weapons and tools.
• They lived in caves of Europe and left beautiful pictures of animals.
• The source states that they did not know agriculture, domestication and socialization.

Homo sapiens sapiens – Modern Man

The source supposes that today’s modern man evolved from Cro-Magnon man about 10 thousand years ago in the region around the Caspian Sea in Central Asia, after which people migrated in three directions.

The final paragraph of page 5 states that the origin and evolution of man might have occurred from ape-like ancestors and gives a sequence including Dryopithecus, Ramapithecus and Australopithecus-like ancestors.

Difference Between Apes and Man

Difference Between New World Monkeys and Old World Monkeys