Darwin’s theory published in Origin of Species is often thought of as the evolutionary theory, having all that there is to say about the case. Biologists, however, know that the theory of evolution has evolved over time. Darwin’s ideas were merged with ideas from genetics to further evolve the original theory to become the Modern Synthesis. Further, since the Modern Synthesis (MS), scientists have made profound discoveries. The double helix structure of DNA, horizontal gene transfer, gene duplication, and chromosome rearrangements, are all concepts discovered after the establishment of the MS. New sciences like biotechnology, bioinformatics and the “-omics” have emerged to cater the vast and rapid expansion of human knowledge. These new …show more content…
They realized that the evolution of animal and plant forms was similar to the development of an embryo into a fully develops organism, they just could not determine the connection. In the early 20th century, biologists were beginning to understand how variation occurred, addressing the missing link of Darwin’s theory. By the 1940s, though the structure of the gene was still unknown, scientists had introduced the idea of the gene into Darwinian Theory. Geneticists clearly saw how heritable material contributed to evolution. All this happened during the Nuclear Age, and as the humans explored the power of nuclear weapons and energy, organisms in the environment became exposed to radiation. Scientists were able to observe genetic changes resulting the exposure. Synthetic chemistry led scientists to find that chemicals could alter the structure of DNA, introducing variation by radiation. These produced random changes in DNA, called …show more content…
Interestingly, MS just missed the boom of the molecular revolution. To the evolutionist, molecular homology is perhaps considered the most substantial evidence of common ancestry and evolutionary relationships (the more similar the molecules, the ancerstries are believed to be), ranking higher up the effectiveness of Darwinian methods. The relationship between homologous genes can be measured by comparing the sequence alignment of their DNA. During this time, biologists have been investigating the possibility that some evolutionary changes occur in a clock-like fashion. Over the course of millions of years, mutations may build up in any given stretch of DNA at a reliable rate. If this rate is reliable, the gene could be used as a molecular clock to estimate divergence dates depends on other methods of dating. Controversial ethical issues emerged from new situations and possibilities brought about by advances in biology and medicine. Mutations, such as those that brought about the concept of MS, daring science experiments, and new medical treatments brought out ethical issues and gave rise to the new concept of