Why did olmec civilization collapse?

Around 400 B.C. La Venta went into decline and was eventually abandoned altogether. With the fall of La Venta came the end of classic Olmec culture. Although the descendants of the Olmecs still lived in the region, the culture itself vanished. The extensive trade networks the Olmecs had used fell apart. Jades, sculptures, and pottery in the Olmec style and with distinctly Olmec motifs were no longer created.

Explanation:

the most famous of all the units fighting in cuba, the "rough riders" was the name given to the first u.s. volunteer cavalry under the leadership of theodore roosevelt. roosevelt resigned his position as assistant secretary of the navy in may 1898 to join the volunteer cavalry. the original plan for this unit called for filling it with men from the indian territory, new mexico, arizona, and oklahoma. however, once roosevelt joined the group, it quickly became the place for a mix of troops ranging from ivy league athletes to glee-club singers to texas rangers and indians.

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