If there isn't enough human birth control this may be where some areas are heading: Presently this might be starting in parts of the middle East

This research on mice might also demonstrate what will happen to humans if they don't practice birth control for any reason on earth. It is a very sobering demonstration of what happens to mammals when overpopulation occurs. Any realistic person should read this to understand better what mankind is presently facing.  The biggest obstacle to people practicing birth control presently is religion. But, it would be the easiest way for the human race to go extinct at present too. We see this presently demonstrated in parts of the Middle East.

 

begin partial quote from:

John B. Calhoun - Wikipedia, the free encyclopedia

 

 

 

Mouse experiments

John Calhoun with mice experiment.

In the early 1960s, the National Institute of Mental Health (NIMH) acquired property in a rural area outside Poolesville, Maryland. The facility that was built on this property housed several research projects, including those headed by Calhoun. It was here that his most famous experiment, the mouse universe, was created.^[1] In July 1968 four pairs of mice were introduced into the Utopian universe. The universe was a 9-foot (2.7 m) square metal pen with 54-inch-high (1.4 m) sides. Each side had four groups of four vertical, wire mesh “tunnels”. The “tunnels” gave access to nesting boxes, food hoppers, and water dispensers. There was no shortage of food or water or nesting material. There were no predators. The only adversity was the limit on space.

John Calhoun meeting Pope Paul VI on 27 September 1973.

Initially the population grew rapidly, doubling every 55 days. The population reached 620 by day 315, after which the population growth dropped markedly. The last surviving birth was on day 600. This period between day 315 and day 600 saw a breakdown in social structure and in normal social behavior. Among the aberrations in behavior were the following: expulsion of young before weaning was complete, wounding of young, inability of dominant males to maintain the defense of their territory and females, aggressive behavior of females, passivity of non-dominant males with increased attacks on each other which were not defended against. After day 600, the social breakdown continued and the population declined toward extinction. During this period females ceased to reproduce. Their male counterparts withdrew completely, never engaging in courtship or fighting. They ate, drank, slept, and groomed themselves – all solitary pursuits. Sleek, healthy coats and an absence of scars characterized these males. They were dubbed “the beautiful ones”.
The conclusions drawn from this experiment were that when all available space is taken and all social roles filled, competition and the stresses experienced by the individuals will result in a total breakdown in complex social behaviors, ultimately resulting in the demise of the population.
Calhoun saw the fate of the population of mice as a metaphor for the potential fate of man. He characterized the social breakdown as a “second death”, with reference to the “second death” mentioned in the Biblical book of Revelation 2:11 ^[1] His study has been cited by writers such as Bill Perkins as a warning of the dangers of the living in an "increasingly crowded and impersonal world".^[2]

Conclusion

Calhoun believed that his research provided clues to the future of mankind as well as ways to avoid a looming disaster. During the 1960s, he and Dr. Leaonard Duhl formed an informal group, the Space Cadets, which met to discuss the social uses of space. The members of this group came from as diverse professions as architecture, city planning, physics, and psychiatry. In Calhoun’s own words “Our success in being human has so far derived from our honoring deviance more than tradition. Template changing always has gained a slight, though often tenuous, lead over template obeying. Now we must search diligently for those creative deviants from which, alone, will come the conceptualization of an evolutionary designing process. This can assure us an open-ended future toward whose realization we can participate.”
Calhoun's book, Environment and Population: Problems of Adaptation: An Experimental Book Integrating Statements by 162 Contributors, was published in 1983.
Calhoun died on September 7, 1995 at the age of 78.^[3]
His papers were donated to the National Library of Medicine by Edith Calhoun and the American Heritage Center.^[4]