The Theory of Evolution Part 1

The Theory of Evolution Part 1 Home

The origin and evolution of humankind and the origin of Human Civilisation

A Brief Look At Evolution - Darwin's notes of evolution

The Theory of Evolution Part 1 To: Part 2

In biology, the continual process by which one form of life changes or evolves into another form. The theory of evolution

suggests that all plants and animals descended from one or several kinds of simple organisms. It also explains why

there are so many different kinds of plants and animals. The inherent characteristics of nearly all living things change

from generation to generation. Eventually the accumulating changes may become so great that the descendant bears

little likeness to it's remote ancestor and may belong to a different species.

Evolution takes place by means of natural selection, mutation and sexual recombination.

Darwinism may be defined as the doctrine of natural selection or the survival of the fitttest as put forward by Charles

Darwin in The Origin of Species, published in 1859. Popularly it is usually regarded as equivalent to the theory of

evolution, often considered only in it's application to one organism - man.

When the theory of evolution first came to public attention in 1859 it was met with a storm of protest and ridicule.

Some people, misinterpreting the theory, thought it claimed that man was descended from apes. Actually, the theory

states that man and apes had a common ancestor that was neither man nor ape.)

Approximately 5 million years ago, the human line and the ape line shared a common ancestor having more or less of

a monkey-like nature from which the apes went on their separate way, leading to modern gorillas, chimps and orang-

utans, and the hominid line ( refers to the human family) went on in another direction, producing the Australopithecus -

line diverges into sub-lines, one of which will eventually give rise to Homo sapiens (modern man)

Man in virtue of his faculty of speech is the highest member of the anthropoids, his nearest of kin being the gorilla,

chimpanzee, orang and gibbon. From a zoological standpoint man differs from the anthropoid apes in 1) his adaptation

to the erect position and the terrestrial habitat, in 2) his greater brain development and in 3) the very fully developed

The oldest living things were simple, one-celled organisms living in the sea.

Started about 600 million years - Life in the oceans originates.No life on earth.

Started about 550 million rears ago - Life exists only in the oceans. Invertebrates evolve. Seaweeds the only plants -

provide food for worms, jellyfish, sponges,....

Started about 500 million years ago - Life exists only in the oceans. Vertebrates evolve. Volcanic eruptions on the floor

Started about 430 million years ago - Life in the oceans develop and the first plants appear on land. New species of

vertebrates develop in the oceans. Level of the oceans rise and new mountain ranges beginning to form.

Started about 400 million years ago - More plants with leaves and roots appear and evolve on earth. Rapid evolution of

vertebrate animals. Ancestors of all fish evolve. Invertebrates - mites, spiders, wingless insects - leave the oceans.

Started about 350 million years ago - Amphibious creatures continue to develop. More plants and trees appear.

Reptiles become the first creatures to breed on land.

Between 40 - 300 million years ago - Life in the oceans and on earth evolving. Development of the oceans, land,

continents, rivers, lakes, mountain ranges and deltas continue, as well as changes in climate conditions.

Animal life is predominantly reptilian. Over time the first mammals evolve from the reptiles. The first dinosaurs appear.

In the following periods reptiles increase in size and variety. Dinosaurs and pterosaurs dominate life on land and in the

Marine life continues to be dominated by reptiles - at a later stage become extinct while many varieties of modern

mammals come into existence - ancestors of the elephant, the rhinoceros, the horse, the pig and cattle. Giant reptiles

Primitive monkeys and gibbons appear and began to evolve into the main groups about 38 - 60 million years ago.

And then in the Oligocene period ( 26 - 40 million years ago) a tail-less primitive ape appears.

In the Miocene period ( 8 - 27 million years ago) the Proconsul, a primitive anthropoid ape living in central africa

In the same period a gibbon-like ape was common in the open plains and less dense forests of Eurasia.This group

is believed to hold the common ancestry of the chimpanzee, gorilla, and humans.

In the Pliocene period ( started 7 million years ago) man-like apes continue to develop. They included the species

known as the Australopithecus. See: Genus Australopithecus.

A large number of fossil bones and teeth have been found at various places throughout Africa, Europe, and Asia.

Tools of stone, bone, and wood, as well as fire hearths, campsites, and burials, also have been discovered and

excavated. As a result of these discoveries, a picture of human evolution during the past 4 to 5 million years has

Ardipithecus ramidus....First known hominid (proto-human) from fossil remains. This species is the oldest known

Possibly the best-known specimen of afarensis is Lucy, a 3.2 million year old partial skeleton found in November 1974

South Africa - A remarkable find was made in 1947 by Dr Robert Broom, who discovered a perfectly preserved adult Australopithecus africanus cranium, belonging to the 2, 5-million-year-old "Mrs Ples", at Sterkfontein. Several hundred

discoveries followed, some dating back 3, 5 million years. Some of the cradles findings include 500 skull, jaw, teeth and

skeletal fossils of early hominids, thousands of other animal fossils, over 300 fragments of fossils wood, and over 9,000 s

Limpopo, South Africa - The Makapans Cave and nearby archaeological and fossil sites are situated on the farm

Makapansgat, 19 km north of Mokopane. It was here in 1948 that the fossil remains of Australopithecus africanus,

a 3, 5 million-year-old ape-man, were found by Raymond Dart.

In more recent years South Africa has once again captured the world’s attention with the discoveries of human remains

at the Klasies River Caves along the Eastern Cape coast. Human remains with anatomically modern features have been

found, dating well over 100 000 years old. If these dates are correct, then it is in Southern Africa that the world's oldest

remains of our own species, Homo sapiens, have been found - some 60 000 years before their arrival in Europe and Asia.

Paranthtropus are a group of hominids that existed at the same time as the Australopithecines.

Ape-like creatures develope enough intelligence to make stone implements. Probably living in Africa.

Primitive man spreads to Asia and Europe.The more recent Homo Genus is thought to arise about two million years ago

and contains sequentially such representatives as Homo habilis, Homo erectus, archaic Homo sapiens, the Neanderthals,

the Cro-Magnons, and finally modern man, sometimes designated as Homo sapiens.

Homo habilis....it is believed that Homo erectus itself developed from Homo habilis. The H.habilis is believed to be the

Evolution of Homo habilis into the "erectines,"a range of human species often collectively referred to as Homo erectus".

Homo erectus....the immediate evolutionary predecessors of Homo sapiens are known as Homo erectus, whose skeletal

remains have been found on several continents and are known by several different popular names such as "Java Man" and

"Peking Man". Although Homo erectus walked upright like humans, used fire, and made crude stone tools, its brain capacity

was somewhat smaller than that of a modern human. The more "primitive" Australopithecus had finally become extinct.

Homo Sapiens ( Archaic )....man's immediate predecessor. Archaic H. sapiens seems to have succeeded at the

Homo Neanderthal....It's mostly accepted that the Neanderthals did not evolve directly into later Europeans or any

other living people, but were replaced by the dispersing moderns, who nonetheless interbred and mixed culturally with the

As the homo species like homo erectus, homo neanderthalis, homo heidelbergenesis and ancient homo sapiens made

further advances in creativity and productivity, they all felt a natural need to pen down their thoughts.

This led to the cave painitngs and carvings. All of those paintings can be interpreted as diary entries as you may see

that the paintings and carvings simply depict what the early men "did" i.e. hunting, using tools etc.

"The 'Recent African Origin' theory rests on a more scientific basis according to which all non-African populations

descended from a Homo sapiens ancestor that evolved in Africa from Homo erectus 100,000 to 200,000 years ago.

These ancestors then spread throughout the world, replacing the archaic Homo-populations, the Neanderthals and the

Homo erectus. The viewpoint is that all genetic lineages derive from a recent common African ancestor and that non-African populations should carry a subset of the genetic variations present in modern African populations.

But a more fascinating theory to me was the one of hybridization. It proposes some gene flow between modern humans

that migrated from Africa with the archaic populations of the Neanderthals and the Homo erectus outside Africa.

So, the evolution of modern humans could have been due to a blending of modern characters derived from the recent

African populations with local characteristics of the archaic populations.

From Homo erectus to Homo sapiens in Africa, the humans spread across a broad geographical region and rapidly

increased in population in the past 50,000-100,000 years." (An Exploration into Early Human Migration)