two

Specifically, seven products had too much arsenic, two had too much lead and 13 had too much cadmium, all above the purity limits set by the U.S.

But only a small part of the genome -- about two percent in mammals -- contains genes, the instructions for making proteins.

A field experiment also showed that snake DNA could be detected in soil where a snake had been resting up to two weeks after its removal.

Most ants have two morphologically differentiated adult castes -- queens and workers -- each irreversibly specialized for either reproduction or nonreproductive altruism such as foraging, defense and care of maternal brood.

How did you two work together to establish that mother-daughter rapport and that prickliness?