Causes of speciation
<span>Geographic isolation
In the fruit fly example, some fruit fly larvae were washed up on an island, and speciation started because populations were prevented from interbreeding by geographic isolation. Scientists think that geographic isolation is a common way for the process of speciation to begin: rivers change course, mountains rise, continents drift, organisms migrate, and what was once a continuous population is divided into two or more smaller populations.
</span>Reduction of gene flow
<span>However, speciation might also happen in a population with no specific extrinsic barrier to gene flow. Imagine a situation in which a population extends over a broad geographic range, and mating throughout the population is not random. Individuals in the far west would have zero chance of mating with individuals in the far eastern end of the range. So we have reduced gene flow, but not total isolation. This may or may not be sufficient to cause speciation. Speciation would probably also require different selective pressures at opposite ends of the range, which would alter gene frequencies in groups at different ends of the range so much that they would not be able to mate if they were reunited.</span>
He La cells have play important role in the study of cancer and even in cancer therapies. He La cells are also used to diagnose trisomic disorders such as Down's Syndrome with the help of chromosome banding. Some genes present in the He La cells are used as markers and compared with the other cell line in question. Presence of the marker for Down's syndrome in the cell in question shows that the person is suffering from the disease.
If pressure less so volume increases and if temperature increase so volume also increases
Answer:
An ectotherm can also be called a Poikilotherm.
:)
Answer:
increase in watervapor hence an increase in rainfall
