Answer:
A. Atmosphere
Explanation:
Atmosphere would be most immediately affected by a decrease in sunlight because sunlight is responsible for the photosynthesis in plants. if sunlight decreases, the photosynthesis reaction is also decreases in plants and less carbondioxide gas is used by the plant from atmosphere for making their food so we can say that atmosphere is greatly affected by the decrease in sunlight.
Answer:
20 million years
Explanation:
If we have a neutral mutation rate of one mutation per 5 million years, then the total of eight mutation between the two different species would be 20 million years. This is because both species will have 4 mutations in those 20 million years, so combined, both by 4, will have 8 mutations between them. So few mutations on so much time will result in two species that are very similar to each other even after 20 million years of evolution, even making them hardly distinguishable, especially if it comes to defining fossil records from them both. A nice example of this are the members of the felidae (cat) family, which are all very closely related, and are almost identical, thus making it extremely hard to distinguish two species of the same or similar size by their fossils.