Answer:
Natural selection
Explanation:
Natural populations have variations. Organisms of a population have various genetic traits. Some of these genetic variations make the organisms better suited to the prevailing environmental conditions. These organisms are more likely to produce more progeny. Over generations, the frequency of the beneficial genetic traits increases in the population due to the higher reproductive success of the organisms with these genetic traits.
This process of differential fitness of organisms of a population where the organisms with adaptive genetic traits have survival and reproductive benefits is called natural selection.
A food chain can usually sustain no more than six energy transfers before all the energy is used up. And so less energy is transferred at each level of the food chain so the biomass gets smaller.
All their children will have heterozygous genes because squidward is "purebred", or homozygous dominant. His wife has to be homozygous recessive for a recessive trait to show up. Every time you cross a homozygous dominant trait with a homozygous recessive trait, you will get heterozygous kids. This means all of them will have light blue skin.