In experiments with phosphorus and sulfur, both of which burned readily, Lavoisier showed that they gained weight by combining with air. With lead calx, he was able to capture a large amount of air that was liberated when the calx was heated. To a suspicious Lavoisier, these results were not explained by phlogiston
Yes, short answer, I can not give you the specifics (consult your biology textbook)
Answer;
A bottleneck effect
Explanation;
When only a few individuals survive unfavorable times, thereby losing the majority of genotypes in the next generation, it is called a bottleneck effect.
It occurs when there is a disaster of some sort that reduces a population to a small handful, which rarely represents the actual genetic makeup of the initial population.
Most humans (and vertebrates, in general) are genetically "programmed" to produce a brown skin pigment known as melanin. Albinism--the inability to produce melanin—is inherited in humans as an autosomal recessive trait. An individual with genotype AA or Aa will have normally pigmented skin, whereas an individual with genotype aa will produce no melanin. The albino's skin is very pale white, and the (highly vascularized) irises of the eyes appear red because no melanin obscures the red reflectance of blood.
The frequencies aa (Parental genotype male) and Aa (Parental genotype female, predict the frequencies of all genotypes and phenotypes expected to result from the cross of an albino male with a heterozygous female.
