One challenge to understanding Earth's geologic history is Most ancient ocean plates have been destroyed by subduction

Plate tectonics causes uplifting

Continents collide and destroy fossil evidence

There are few continental plates older than 200 million years old

Continents collide and destroy fossil evidence

Explanation:

One main challenge in understanding earth's geologic history is that continents collide and destroy fossil evidence.

the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

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