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.
Meter is the SI unit for length. :)
A. Neutral water
Less than 7 is acidic (which has 6 letters, 6< 7)
More than 7 is alkaline (which has more than 7 letters). Alkaline = basic
7 is neutral
Absorb more thermal energy, and the rough surface will prevent it to reflect efficiently.
Ecosystems can be large and are made of biomes. Some examples of ecosystems are deserts and forests.