The content you've requested is available without charge only to active Sigma Xi members and American Scientist subscribers.
If you are an active member or an individual subscriber, please log in now in order to access this article.
If you are not a member or individual subscriber, you can:
Many cells and tissues of the body have an ideal temperature at which they perform best. Muscles are most efficient a few degrees above their resting temperature, hence the need for a warm-up before a rigorous workout. Neural tissue, on the other hand, is very sensitive to rising temperatures—an increase of only 4-6 degrees Celsius can disturb brain function, leading to convulsions and even death. To avoid such catastrophes mammals have evolved elaborate physiological mechanisms to regulate their core body temperatures (about 37 degrees). Unfortunately this core temperature is about three degrees above the ideal temperature for the production and storage of viable sperm cells. Many terrestrial mammals have solved this problem by using a scrotum, which holds the sperm-producing testes away from the heat of the body. However, two groups of marine mammals, cetaceans and seals, do not have a scrotum; they maintain their testes inside the body where they are surrounded by tissues that can generate heat. How then do marine mammals keep their sperm alive? It’s a mystery that Rommel and his colleagues solve in the course of their anatomical and physiological explorations of dolphins and seals.
Connect With Us:
An early peek at each new issue, with descriptions of feature articles, columns, and more. Every other issue contains links to everything in the latest issue's table of contents.News of book reviews published in American Scientist and around the web, as well as other noteworthy happenings in the world of science books.
To sign up for automatic emails of the American Scientist Update and Scientists' Nightstand issues, create an online profile, then sign up in the My AmSci area.
JSTOR, the online academic archive, contains complete back issues of American Scientist from 1913 (known then as the Sigma Xi Quarterly) through 2005.
The table of contents for each issue is freely available to all users; those with institutional access can read each complete issue.
View the full collection here.
Receive notification when new content is posted from the entire website, or choose from the customized feeds available.