Jean Baptiste Lamarck put forth the theory of inheritance of acquired characters, which is also known as Lamarckism. It was published in 'Philosophie Zoologique' in the year 1809. The four propositions of Lamarckism are as follows: a. Living organisms and their parts tend to increase in size continuously due to internal forces of life. b. New organs are formed in [...]
A reproductive isolating mechanism is a structural, functional, or behavioural characteristic that prevents successful reproduction from occurring between different species. This helps in accumulating genetic variations in species. If reproductive isolation does not exist, variant forms freely interbreed with the normal forms and this would lead to intermixing of their genotypes. These mechanisms are of two types: 1. Pre-Mating Mechanisms: [...]
In this article we will discuss about the Darwinism theory of evolution with its criticism. In 1831, Charles Darwin on a voyage on HMS Beagle for five years noted the flora, fauna and geology of the islands of the South Pacific and collected numerous living and fossil specimens. He also sailed to the Galapagos Islands about 600 miles from the [...]