Answer:
Environment and competition is the leading cause of evolution. It's an instinct to want to live, but trying to survive is difficult when other animals have the same goal. An ecosystem is a cycle, but every generation of this ecosystem slightly changes, and so do the animals. Every bug that has fitness can start overpopulating the ecosystem, leading to a surge of resources for what preys on the bug. Now bird's population goes up, so do other animal populations. Or the bug becomes an invasive species, and birds are being hunted too often to decrease the population.
In a different scenario, bugs are evolving because of the selection pressure that the environment is giving them. The birds have become better over the generation, and now have a more suited beak to catch the bug off the ground. The bug population maybe be decreasing, but the ones who live through the crisis are populating with bugs that certain gene that helped them out. But it's not over, the bug population isn't declining but it wasn't as big as it was before. The bird will find more ways to find and capture the bugs. But then bugs will keep surviving through the selection pressure and become much harder to find since they figured out camouflage. The bug that was neon yellow was dying since they were easy to see. Now they can range from green to black to hide in the environment. Now the birds are facing the selection pressure, it's a cycle.
(look, im not good at gammar, so you should get this looked at before entering it. I put it through gammarly if that helps.
The answer is Both result in a change in allele frequencies in the affected population
Genetic drift is a change in the frequency of alleles in a population as a result of random sampling of organisms. I<span>magine you have two different alleles in the population responsible for red and white color of a flower. Their allele frequencies are 0.2 for white flowers and 0.8 for red flowers. After some change in the environment, only white flowers survive. They will reproduce, and in the population, there will be only white flowers. The population for these flowers will increase from 0.2 to 1.
Speaking of gene flow, it is not as dramatic and drastic as genetic drift, but still, it includes a transfer of alleles from one population to another, so there is expected a change in allele frequency.</span>
The ecological pyramid is smaller at the top due to the lower amount of species to fit into the category (diversity is decreased, and the higher, the more suppressed the energy is in the animals/species).
Answer:
A. the digestive, muscular, and respiratory
Explanation:
Muscle weakness affects the muscular system (muscles are in the muscular system) , stomach pain affects the digestive system (stomach is a part of the digestive system), and coughing affects the respiratory system (coughing hinders the ability to breathe properly).