The answer you are looking for is Natural Selection.
Answer:
He can infer that beriberi may be related to diet, but more and better studies are needed
Explanation:
They decrease because the zebra mussel were taking their resources. Leaving them nothing to eat.
Asteroid impact
Volcanic eruptions
Explanation:
Asteroid impact and volcanic eruptions are two common events that could lead to a mass extinction.
A mass extinction is an abrupt decrease in life on earth due some catastrophic event.
- The collision of a large bolide on the surface of the earth is a catastrophe in itself.
- The collision and its aftermath have destructive consequences on life.
- The force of the collision can reverberate in form of vibration throughout the earth.
- It can cause heating of the earth surface.
- Volcanic eruptions can become global phenomenon that upsets the earth balance.
Learn more:
Extinction brainly.com/question/10860460
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