While evolution is unpredictable, science aims to quantify it and the latest surveys of marine life have shown a new pattern, the size of marine animals are increasing. The marine animal has gone up by a factor of 150, this has happened in the past 542 million years (since the Cambrian period).
There is a vast magnitude of variables that scientists are trying to understand and the concept of “drift” is not part of them and does not explain this pattern. The process of natural selection is not new. It was first proposed in Cope’s rule after Edward Drinker Cope, an American fossil specialist.
Palaeontologists discovered that modern mammals are bigger than their ancestors, this discovery was made in the 19th century but this pattern does not show consistency through the animal world, for example, birds grew smaller while dinosaurs grew bigger until they got extinct
Some scientists think that this trend is not solid enough to influence the assumption that every animal in the planet will evolve to grow bigger. Diversity and expansion were one of the main reasons why the marine life has grown larger.
It could be a matter of chance or an evolutionary advantage; scientists are currently trying to work out to answer this question. The marine animals have become faster and better predators, scientists have used computer models and have ran simulations to understand the evolutionary process, the size advantage has matched the fossil history making the “size advantage” theory a plausible theory.
Researchers are trying to find out what the benefits of “extra size” could be, according to them it could be to eat a larger prey or burrow.