If you hit $0 Avail. funds for trading, your account will go into a margin call and Ameritrade will force you to sell positions or deposit money. I'm going to assume your Account Balance isn't -8.1k because you would have hit a margin call long before your account went negative unless this all happened overnight.
Sadly, these peaceful animals may not survive into the next century. Ape conservationists say time is running out, as there are only about 720 mountain gorillas left in the world, and the majority of gorilla populations are plummeting.
Mountain gorillas are one of our closest relatives, sharing 98.6% of our genomes and 99.6% of our DNA. Humans and gorillas evolved from a common ancestor, and like human beings, mountain gorillas are intelligent, playful, emotional, and family-oriented. They are even capable of learning sign language.