In the female pig reproductive cycle, more number of eggs are released during one ovulation cycle. That is why, the number of offsprings born is more. The father of the litter is same single animal only. Because the process of fertilization of sperms with the eggs released happen in a time duration of few hours only.
In case of humans as well, the father is same. This is because in human reproductive cycle, only one egg is released majorly, accept the case of fraternal twins where two eggs are released and both are fertilized by two different sperms, but again from the same father.
Hypothalamus
When there is abnormally high internal temperature, sensors
in the Central Nervous System send signals to the hypothalamus. The hypothalamus initiates thermoregulation
by sending messages to various organs and body systems with a various
mechanisms. High temperature will set off sweating and vasodilation to cool down
the body.
Populations have a genetic variation among individuals and that is important to the populations ability to survive in different situations that have an affect on the natural selection. There are different factors which can increase or decrease the genetic diversity, and influencing natural selection. These factors can include an environmental factor, one of the major factors, which can cause changes in the genetic variation of a population and influence the natural selection. A famous and important example of the environmental factors affecting natural selection was made during the industrial revolution when many more gray moths made up the moth population. This was so that they could blend in with the soot from factories to avoid predators.
