Answer:
They digest without the use of teeth.
Explanation:
The food trickles from the crop into the bird's stomach (proventriculus or gizzard) where digestive enzymes are added to the mix and physical grinding of the food occurs. The gizzard is why chickens do not need teeth.
Hey i think the answer is A
To test for the keystone species hypothesis, the wolves in another region can be removed or trees can be reintroduced to see the effect on the ecosystem.
<h3>What is a keystone species?</h3>
A keystone species is an organism whose existence defines an entire ecosystem such that them, the ecosystem would be severely affected or may not exist.
Trophic cascades are events which result in serious distortions in an ecosystem as a result of the removal or addition of a top predator.
To test for the hypothesis of keystone species and trophic cascades, the wolves in another region can be removed or trees can be reintroduced to see the effect on the ecosystem.
Learn more about keystone species at: brainly.com/question/2044051
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