common descent means the evolutionary in biology and how they have something linked with their common ancestors.
Mussels are molluscans and are freshwater animals. The change in the environment led to new traits of mussels, it underwent natural selection and the thick shells have high chances of survival.
<h3>What is natural selection?</h3>
Natural selection is a process of nature that eliminates the organism with less survival and unfit traits while selecting the organisms with better traits of survival in the altered conditions.
The arrival or the introduction of the crabs in the environment altered the previous habitat of the mussels and led to the adaptation of the better trait quality in the mussel species.
The trait of the thick shells underwent natural selection as they were favoured for the changed conditions. The mussel having thick shells have high chances of survival over thin-shelled mussels as the crab will find it hard to attack the thick-shelled mussels.
Therefore, option A. change in environment, option B. natural selection and option E. chances of survival are the correct statements.
Learn more about the natural selection here:
brainly.com/question/10715606
Answer:
b. 10,000 plants
Explanation:
Producers, plants, contain the most stored energy in an energy pyramid.
I hope this helped :)
Answer: Energy is not recycled once it passes from producer to consumer to decomposer.
The energy flow in an ecosystem in the form of food from one organism to other is food chain. It comprises mainly of three types of organisms producers or autotrophs, consumers or heterotrophs and decomposers. The energy flow in food chain or food web is unidirectional from plants which are the primary producers to primary consumers or herbivores, then to secondary consumers or carnivores and finally to the decomposers. On its unidirectional flow the energy is lost in different form such as heat loss, decay, respiration etc. The energy passed from one level to another is not the same and gets lost in the process so when the energy is received from one tropic level to another it is always less than that received by the previous tropic level.
