This type of reproductive strategy is advantageous because it allows females to reproduce almost continuously and allows for almost immediate replacement of lost young. The strange male is likely to be infanticidal towards newborn young that he has not sired. By aborting her developing litter, a female can quickly mate with the new male and produce young, rather than wasting time and energy gestating a litter that is likely to be killed. Each form of mammalian locomotion is associated with numerous anatomical specializations. Contrast the specializations of the limbs and tail typically found in arboreal species with those found in marine species.
Prehensile tails are also common.
Describe five characteristics of early mammals and indicate how each of these contributed to the success of mammals relative to their therapsid ancestors. Heterodont dentition, secondary palate and other characteristics that were found in both early mammals and therapsids only received partial credit, since these characteristics could not be responsible for the success of mammals over therapsids. Evaluate this definition based on your knowledge of mammalian characteristics. Although each component of the definition considered alone is not effective in differentiating mammals from other vertebrates, taken as a whole the definition successfully excludes all non-mammals. Thus, none of the components of the definition is diagnostic.