Men and women within one human subtype differ from each other in the same way as females and males within one subspecies of, for example, animals. They have identical personal characteristics, psychophysiological algorithms, lifestyle, and functionality. Some differences might be present in the sexual factor; for example, in attitudes towards offspring. In nature, females of some species of animals care for their offspring without participation of males; females make males leave their offspring; not only males, but also females of some species do not engage in caring for their offspring at all; or, for example, a male and a female of some types of birds engage in upbringing of their nestlings together and distribute parenting duties equally. However, as mentioned above, these differences are not fundamental.