Hi
It is true that on the Galapagos islands Darwin observed tortoises with a dome and saddle shaped shells, you can see both in attached image.
Darwin observed that Galapagos Tortoises had the shells with different shapes depending on the Island they live, For example: The tortoises with saddle shaped shells were able to reach up to eat leaves of plants while the tortoises with dome shaped shells would not reach up and they would eat food from on ground sources. This made him think that the differences in tortoise shell is also a strong evidence that indicates that how tortoises have adapted themselves to better get their food as per the available resources and how they have evolved from same ancestral specie into two different species. This point also helped him in proposing the theory of evolution by natural selection.
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Most of the worlds deserts are located at latitudes where cold, dry air moving toward the poles descends.
E) cold, dry air moving toward the poles descends.
<u>Explanation:</u>
A large portion of the world's deserts are situated almost 30 degrees north scope and 30 degrees south scope, where the warmed tropical air starts to drop.
Hot deserts are essentially found around the Tropics of Cancer and Capricorn. As air moves inland, it gets drained of dampness and precipitation drops. So the majority of the world's deserts are situated at scopes where cool, dry air advancing toward the shafts slides.
Answer:
Mutation is the source for new genetic variation: Genetic variation is brought about by random mutation. Without mutation, genetic variation cannot occur. Mutation is a change in the genetic code in DNA and can lead to a change in the protein that is coded for that segment of DNA.
Explanation:
Mutations are changes to an organism's DNA and are an important driver of diversity in populations. Species evolve because of the accumulation of mutations that occur over time. ... This mutation has introduce a new allele into the population that increases genetic variation and may be passed on to the next generation.
Past climate changes led to extinction of many species, population migrations, and pronounced changes in the land surface and ocean circulation. The speed of the current climate change is faster than most of the past events, making it more difficult for human societies and the natural world to adapt.
Hello There!
A drug is any chemical substance that alters the body physically or mentally for a non - nutritional purpose.
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- Hannah ❤
