By dating the rocks in the ever-changing crust, as well as neighbors such as the moon and visiting meteorites, scientists have calculated that Earth is 4.54 billion years old, with an error range of 50 million years.
The correct answer that would best complete the given statement above would be the term ADAPTIVE RADIATION. African cichlids are a group of closely related fish species. There are at least 500 known species living in three small lakes. Over time, specialized teeth and body colorations have evolved for each species in response to mutations and competition for food and mates. This change over time is an example of ADAPTIVE RADIATION. Adaptive radiation by definition, is <span>the diversification of a group of organisms into forms filling different ecological niches.</span>
A population decrease in primary producers would affect the ecosystem negatively because everyone who ate the primary consumers would have a lack of food.
<span>the study of living organisms, divided into many specialized
fields that cover their morphology, physiology, anatomy, behavior,
origin, and distribution.</span>
