There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms.
There are problems with each of these methods. The fossil record is like a movie with most of the frames cut out. Because it is so incomplete, it can be difficult to establish exactly when particular evolutionary changes happened.
Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. Confounding factors rack up for species that are very distantly related, making the earlier dates more uncertain.
These difficulties mean that the dates in the timeline should be taken as approximate. As a general rule, they become more uncertain the further back along the geological timescale we look. Dates that are very uncertain are marked with a question mark.
I think the correct answer from the choices listed above is option B. The difference in biodiversity between the tundra and the tropical rain forest would be that warmer temperatures and higher average rainfall in the tropical rainforest allow more things to survive. Hope this answers the question.
Global winds are winds that appear in belts that go all around the world. Like local winds, global winds are driven by unequal heating of the atmosphere. Since global winds blow west to east, it helps humans travel west to east.
<h3>How global winds influence climate?</h3>
Global wind belts and calm regions have an effect on, is that the berg winds blow from the east and die out as they are available close to the equator.
The westerlies blow from the west and move storms across u. s. The easterlies blow from the east and they cause stormy weather to occur once cold air forms this belt meets heat air of the westerlies.
Thus, this could be the answer.
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A all cells have the same number of chromosomes hope this helps!! and C
I believe the answer is most likely
C): 4
I hope this is correct and helps
