Why do different animals have different fertility?

1) The more expressed the care of the offspring, the less fertility.
2) For all organisms there is a pattern: the greater the likelihood of death of offspring, the greater the fecundity.
3) The larger the animal, the less fertility.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.