<em>A natural disaster. </em>
Explanation:
A natural disaster would most likely have occurred to have the population of squirrels completely diverge from each other in order for them to become two separate species.
If a tornado, flood, earthquake, or another type of a natural disaster were to happen, it may have caused drastic damage to the ecosystem and environment of the squirrels. This would most likely cause the squirrels to split up, or diverge from each other and go to separate places in search of a new home.
Over time, these squirrels will reproduce with their own group. Each new group of squirrels, as they are both in different environments now, will have different adaptations from each other. This will eventually make it so they will never be able to reproduce with each other again if they were to meet, as they are now completely different species of squirrel.
Answer:
Deserts
Explanation:
Short for desertification
Well, an endoskeleton is an internal skeleton, like humans have.
Pro: Bones do not get broke as easily, since they are inside of the body. Bones that break also heal more quickly in an endoskeleton, since they have tissue and blood surrounding it and transferring nutrients.
Con: The flesh can get easily damaged. There is no shedding with endoskeletons, so a new skeleton cannot be grown in the event of an injury.
Answer:
The answer is A.
Explanation:
Since only 1 of the options is wrong, i assume you are looking for that one.
Two types of immunity systems, innate immunity and adaptive immunity. Adaptive immunity is formed when it is exposed to a harmful substance, vaccines for example create adaptive immunity.
Innate immunity is present at birth which consists our skin protects us physically, chemical substances in our blood that protect us from bacteria and infections and also our blood cells such as T cells.
Since innate immunity forms one of the first lines of defense in our immune system and is the first to respond to a threat in a few hours down to as little as minutes, it is not slower than adaptive immunity in its response to infections and pathogens.
I hope this answer helps.
