Heredity and Evolution – Evolutionary Relationships II
* Homologous and analogous characteristics help identify an evolutionary relationship between different species.
* Fossils are an important evidence of evolution.
* Evolution of eye in different species is an example of biological convergence.
* Reptiles and birds have evolved from a common ancestor through adaptation.
* Different vegetables are descended from the wild cabbage ancestor.
Origin of Life
* The origin of life is interlinked with the evolution of the earth, which is linked with the evolution of the universe.
* The universe is vast and comprises many galaxies and is almost 20 billion years old.
* The Big Bang Theory refers to a singular huge explosion which caused the infinitesimally small, hot and dense universe to expand and then cool.
* Panspermia is the oldest theory expounded by the Greeks which assumes that units of life called spores were transferred to different planets.
* The theory of Spontaneous Generation believed that life came out of decaying and rotting matter such as straw and mud.
* Louis Pasteur founded the theory of Biogenesis, which explains that life comes only out of pre-existing life.
* The theory of Chemicals Evolutions, which states that the first life forms arose from non- living molecules through evolutionary forces, is now widely accepted.
Origin and Evolution of Humans
* Man, chimpanzees, gorillas, orang-utans and human beings are four memberspecies of the hominidae family.
* Dryopithecus was a genus of ape that lived in East Africa, Europe and Asia around 25 to 9 MYA.
* Ramapithecus was a primate that lived between 2 million and 14 million years ago.
* Australopithecines lived in the grasslands of East Africa, Europe around 2 MYA.
* The first human- like being was Homo Habilis who lived in sub- Saharan Africa between 2 million and one point 5 MYA.
* Homo erectus were human beings of medium stature two walked upright and flourished till about 200000 years ago.
* Neanderthal Man, with brain size of 1400 cubic centimetres lived in Europe,
* Northern Africa and Eastern and Central Asia between 100000 and 40000 year ago.
* Homo sapiens sapiens evolved between 75000 and 10000 years ago during the Ice Age.
