A team of scientists from Stanford University (USA) found that the average size of marine mammals has enlarged 150 times over the past 55 million years. Survey of American scientists proves the rule Cope, according to which the animals ultimately increase in size. Paleontologist Edward Cope came to this conclusion at the end of 1800, noting a tendency to enlarge the size of land animals, such as horses.
Amusingly, the trend of increasing size are subject not all animals. So dinosaurs grew, and birds and insects – no. The process of increasing perhaps was the effect of random evolution that occurred not through natural selection – a process known as neutral drift.
The researchers analyzed data on more than 17,208 diverse groups of marine animals, arthropods, brachiopods, echinoderms, mollusks and chordates (including all mammals, fish and reptiles ). The average volume of the body of animals has enlarged 150 times.
Amusingly, those species that ultimately rose have become more diverse and therefore more successful in the animal kingdom.
Reptiles and marine mammals have been and are major heavyweights of our planet. Giant dinosaurs inhabited the sea in the Mesozoic era (252-66 million years ago), and vast marine mammals that live in the oceans to this day, are the biggest creatures on Earth. The undisputed champion of the weight and size is the blue whale, the weight of which can exceed 150 tons. The study authors note that the gigantism of marine reptiles and mammals associated with their basis from terrestrial animals and breathing oxygen.