When species are extensively hunted, individuals that reach reproductive maturity early make up a larger proportion of the population, because they have a better chance of reproducing  When species face diminished food resources, on the other hand, individuals tend to take longer to reach reproductive maturity
These considerations may help settle whether the primary cause of the gradual disappearance of North America' s mastodons, prehistoric animals related to elephants, was diminished food resources or human hunting, since
from the location of certain hunting weapons in juxtaposition with mastodon remains, it is possible to determine whether those weapons were used to hunt mastodons