EVOLUTION OF LONGEVITY IN TETRAPODA: SAFETY IS MORE IMPORTANT THAN METABOLISM LEVEL

Abstract

Various environmental morphological and behavioral factors may be decisive in the longevity of representatives of various taxa. Long-lived species develop systems aimed at increasing the body’s stability and defense, and ultimately increasing life expectancy. In addition, long-living species are characterized by different levels of manifestation of factors favorable to longevity (gerontological success): body size, slow metabolism, level of activity of the body’s repair systems and antioxidant defense systems, resistance to toxic substances and tumor formation, and the presence of neotenic characteristics. Continuing the work on mammals, in this work we studied the characteristics that distinguish long-lived ectotherms (crocodiles and turtles) and compared them with those of other representatives of ectotherms (squamates and amphibians) and endotherms (birds and mammals). The article also discusses mathematical indicators used to assess the predisposition to longevity in different species. These indicators include both standard ones (mortality rate, maximum lifespan, coefficient of variation of lifespan) and derivatives from them. evolutionary patterns of aging are further explained by protective phenotypes and life history strategies. The work assessed the relationship between lifespan and various studied factors, including body size and temperature, encephalization, protection of occupied econiches, the presence of protective structures (for example, shell and osteoderms), environmental temperature, etc.), and their influence on the distribution of lifespan as a statistical quantities. The hypothesis about the level of metabolism and temperature as the most determining factors of longevity was not confirmed. It turned out that animals protected by shells (turtles with their exceptional longevity) live longer than species that have poison or lack protective devices. The improvement of methods of defense against external threats in long-lived ectotherms is consistent with the characteristics of long-lived endotherms (for example, naked mole rats that live in tunnels underground, or bats and birds, whose ability to fly is also one of the best methods of defense).