Animals Become 'Larger' Through Generations

Researchers say that animals are becoming 'larger' in their evolutionary process. According to a report by AFP, the findings of this research were published on Friday, February 19, in the journal 'Science'. For example, the average size of aquatic animals has increased 150 times over the past 542 million years. 'Noel Heim', a researcher at Stanford University's Environmental, Energy, and Earth Sciences Laboratory, stated: 'The size difference is similar to the difference between a five-centimeter-long sea squirt and a thirty-centimeter-long sea squirt; it may not seem like much, but it indicates a significant leap.' Scientists first observed the growth of animal body sizes in fossils dating back 550 million years. However, according to 'Jonathan Payne', a biological paleontologist and head of the research team, scientists have been aware of the size differences between modern animals and their early ancestors for some time: 'We have known for a while that the largest organisms today are larger than the early examples that existed when life first appeared on Earth.' This type of change is not true for all animal species and is mainly observed among larger and more diverse species in the early stages of evolution. Payne explained that 'for reasons we do not fully understand, larger animal species have become more diverse over time compared to their early generations.' The recent research also confirms 'Cope's Law', named after 'Edward Cope', a 19th-century paleontologist. According to 'Cope's Law', animal species gradually become larger over time. Cope had noticed that mammals, including horses, grow larger over several generations. Scientists had previously attempted to prove Cope's theory in other organisms, but the findings from each test were contradictory and unreliable. For example, corals and dinosaurs, according to Cope's theory, grew larger over generations, but birds and insects did not follow this law. As a result, some scientists questioned the existence of this evolutionary principle among terrestrial animals. With such a background, Jonathan Payne's group decided to conduct the most comprehensive test of Cope's theory. The research team examined a database containing information on over 17,000 animal groups, including aquatic animals, arthropods, and mollusks, over a 542 million-year period. Ultimately, the findings of this research confirmed Cope's theory. According to 'Noel Heim', data related to about 75% of aquatic animals and 60% of animal types that have existed since the dawn of life were included in this study.