Testicle fetal abdomen to the inguinal ring and beyond to the inguinal canal and into the scrotum. In most cases (97% full-term, 70% preterm), both testes have descended by birth. In most other cases, only one testis fails to descend (cryptorchidism) and that will probably express itself within a year. The testes grow in response to the start of spermatogenesis. Size depends on lytic function, sperm production (amount of spermatogenesis present in testis), interstitial fluid, and Sertoli cell fluid production. After puberty, the volume of the testes can be increased by over 500% as compared to the pre-pubertal size. Testicles are
Collapse: How Societies Choose to Fail or Succeed Collapse: How Societies Choose to Fail or Succeed Collapse: How Societies Choose to Fail or Succeed (titled Collapse: How Societies Choose to Fail or Survive for the British edition) is a 2005 book by academic and popular science author Jared Diamond, in which Diamond first defines "collapse": "a drastic decrease in human population size and/or political/economic/social complexity, over a considerable area, for an extended time." He then reviews the causes of historical and pre-historical instances of societal collapse — particularly those involving significant influences from environmental changes, the effects of climate change, hostile neighbors, trade partners, and the society's response