Why do many species that existed 35 million years ago no longer exist?

I'm not an expert but I guess 1 reason is the earth quakes volcanoes etc and also human beings as they hunt species and this causes species and also the extraction of natural minerals and substance like trees etc that animals can live in and toxic substances that comes from factories.

representative government

while it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton.

explanation:

before eli whitney's invention of the cotton gin, picking and cleaning cotton was a slow, labor-intensive job. workers, usually slaves, had to pick the seeds from the cotton fibers by hand. this invention made it possible to grow large amounts of cotton on big farms and make money.