Question

Both Darwin and Lamarck proposed mechanisms by which species might evolve. Although Darwin first published his ideas in the mid-1800s, most scientists continued to favor Lamarck's explanation until near the end of that century. What was the most likely cause of the eventual shift from Lamarck's hypothesis to that proposed by Darwin?

Answer 1

The shift to Darwin's theory of evolution occurred as new genetic evidence emerged against Lamarck's idea of the inheritance of acquired characteristics, and the understanding that geological and evolutionary changes occur gradually over time, supported by the work of Hutton, Lyell, and Malthus.

Step-by-step explanation:

The shift from Lamarck's hypothesis to Darwin's theory of evolution by natural selection was influenced by new scientific evidence and the understanding that species change over time through inherited genetic variation and natural selection, not by the inheritance of acquired traits as Lamarck had proposed. Lamarck's idea of the inheritance of acquired characteristics was eventually discredited as it was contradicted by emerging genetic evidence.

The accumulation of evidence from various fields including geology and understanding about the age of the earth, as presented by scientists like James Hutton and Charles Lyell, along with Thomas Malthus's work on population growth, further supported the idea of a long process of evolution through natural selection, as proposed by Darwin.

Furthermore, discoveries in the field of geology promoted the idea that Earth's history is marked by gradual change rather than catastrophic events, which paralleled the concept of gradual evolution in living organisms. The overproduction of offspring seen in natural populations, noted by Darwin from Malthus's writings, contributed to the concept of a 'struggle for existence', which forms a cornerstone of Darwin's theory.

As a result, Darwin's mechanism of evolution became increasingly accepted by the scientific community as it provided a more robust explanation for the observations and data being collected.

Answer 2

The correct answer would be "presence of a large number of pieces of evidence which supported Darwin's theory as compared to the number of evidence which supported Lamarck's theory".

Lamarck theory was about the inheritance of acquired characteristics whereas the idea of Darwin was about the inheritance of traits randomly acquired by organisms which are then selected naturally or pressure of the environment.

Later, it was proved that acquired traits such loss of tail, injury, skills et cetera do not pass from parents to the offsprings.