Question

Explain the differences between the evolutionary theories of Charles Darwin's natural selection and Lynn Margulis Endosymbiosis. Are the theories testable and expensive, according to Steven Gould's standards? Does the apparent contradiction between the theories weaken or strengthen the theory of evolution? Why or why not? Feel free to address Michael Pollan's discussion about planets and Lovelock's Gaia theory to round out your ideas.

Answer 1

Charles Darwin introduced the idea that natural selection is the driving force of evolution. Natural selection is the evolutionary mechanism that results in adaptive evolution that is genetic makeup of populations change with time to adapt to their environment. It is based on ‘survival of the fittest’. There were certain challenges to Darwin’s theory. One was Lynn Margulis’s endosymbiosis theory. It explained that evolution occurs due to the symbiotic forces, that is, cell organelles arise from symbiotic associations between heterotrophic cells and autotrophic cells (mitochondria). The main difference among these two theories is that natural selection only causes variations among species or populations and Lynn Margulis describes that symbiotic relations cause evolution. Margulis tried to emphasize on novelty however according to Darwin’s theory, the only source of novelty is random mutations.

These mentioned theories are testable through generation of a testable evolutionary hypothesis and experimental design with the help of evolutionary trees. The contradiction between these theories may explain the origins of diversity on Earth. The experiments would give updation on evolutionary theories. Still the researchers are in dilemma on how errors or damages can cause variations in living beings on Earth. They have to focus on other fields including natural processes such as molecular biology and cell biology.