The columbian exchange irrevocably

homogenized the world's biological

landscape. what does john green mean by

this?

Ever since Columbus set foot in the Americas, the number of endemic species, that is to say, species that only live in a specific geographical area has diminished, while other species have thrived, in the five continents.

For example, the Columbian Exchange led to the cultivation of a South American crop: the potato, across Europe and Asia, where millions of people in cold climates where able to avoid famine by feeding themselves with it.

Another biological homogeneization process occurred with disease vectors: before the Columbian Exchange, diseases such as measles or smallpox were unheard of in the Americas. When Europeans arrived, Native Americans did not have defenses against this illnesses, and the majority of them perished because of contagion (over 90%).

Nowadays, these diseases are present all over the world, but thanks to vaccines, they do not kill as many people as before.

Explanation:Ashoka sent Buddhist missionaries to the four corners of Asia to spread the religion, led pilgrimages to all the Buddhist sacred places, repaired old shrines, stupas and built new ones. he was a tolerant ruler.Emperor Asoka (born 304 B.C.,ruled 274-236 B.C.) was arguably the greatest ruler in Indian history and was the man who ensured Buddhism success as a world religion. After Asoka conquered the kingdom of Kalinga, in one of most important battles in the history of the world, near the Brubaneswar airport in the state of Orissa, he was so appalled by the number of people that were massacred (perhaps 100,000 or more) he converted himself and his kingdom to Buddhism and sent Buddhist missionaries to the four corners of Asia to spread the religion. The wheel Asoka used to symbolize his conversion to Buddhism is the same one pictured on India's flag today.