Top Highlights

• The reasoning is exactly the same. Arctic peoples divert less of their food into energy, and more into heat. This may not matter in most circumstances (they just eat more) but it matters in one instance: sperm motility. Sperm are powered by their mitochondria as they swim towards the egg, and because there are fewer than a hundred mitochondria in e...
• The problem is that the flatworms all want to be male.
• the male mating strategy—of spraying sperm—is often adopted by the entire species, leading to such bizarre mating conflicts as penis fencing flatworms.
• Females and males have their own ideas about when to mate, and with whom; males tend to be keener, females choosier. The outcome is an evolutionary arms race in which each sex exerts an influence over the adaptations of the other, countering some of the more preposterous
• between the sexes: the female sex passes on organelles, the male sex does not. The result is uniparental inheritance