Constant mortality and fertility over age in Hydra

Vaupel’s Opus magnum on Hydra and negligible senescence (Schaible et al., 2015, PNAS):
http://www.pnas.org/content/112/51/15701.short

“How an organism changes with age and why the pattern of change differs across species are questions that have intrigued biologists since Aristotle. Patterns of change can be described by trajectories of birth and death rates over age. For humans and many other mammals, mortality increases and fertility declines with age among adults. For other species, however, a remarkable variety of patterns has been observed. Although roughly constant mortality and fertility trajectories have been reported for some species, the data are problematic because sample sizes are small, especially at older ages. Here, we present compelling evidence for constant mortality and reproduction of Hydra using data from careful, large-scale studies over 8 y with 2,256 individuals.”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s