Before coming up for air, seals can remain underwater for upwards of
a. 1 hour.
b. 1.5 hours.
c. 2 hours.
d. 2.5 hours.

What are two reasons for why a species might disappear from the fossil record?

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons

The offspring of two different species