Darwin’s theory of Natural Selection was accepted for a long time but later on, several objections were raised against this causo-mechanical explanation of the origin of new species. Some of the important objections are —
1. Darwin could not distinguish between heritable and non-heritable variations, also, he did not explain the origin of variation.
2. The Natural Selection can not be considered as a sole ca use for the origin of new species but the new species originate as a result of mutation.
3. The Natural Selection does not explain the effect of use and disuse and the presence of vestigial organs.
4. He has described the survival of the fittest only but not the arrival of the fittest in any form.
5. Darwin believed in Blending inheritance i.e. the offspring should resemble their parents. He had no idea of Particulate inheritance.
6. He believed in small and fluctuating continuous variations.
7. The Pangenesis theory was criticized.
8. Several differences between species are not of adaptive value.
9. No explanation for over specialization was given, as in dinosaurs.
10. The sexual selection theory proposed by Darwin was considered inadequate.
On the basis of objections raised by Bateson, Hogben and some others the death of Darwinism from the Biological laboratory was proclaimed. But, all the objections are not considered very serious at present and Darwinism is supposed to be very much alive even today.