Alien
a species not native to a particular area (A3, C4, R5)
Adaptive radiation
the rapid development of many species from a single ancestral population (A3, R2, R3, IS1)
Adaptive optics
telescope equipment that compensates for the effect of turbulence in the lower atmosphere as well as high above the earth’s surface (A5)
Adaptation
a change in an organism or species that enables it to survive in a particular habitat (A3, C3, R3, M2, M3)
Absolute Age
in geology, an age given in numbers as opposed to an age expressed relative to other geological formations (A1)