think-tac-toe project: crossword puzzle

An online crossword puzzle with 12 words. Play it free at AgileCrosswords.com.

Clues

A body part with the same basic structure and embryonic
the process by which individuals that are better adapted to thier enviroment are more likely to surv
Marked difference from the normal or recognized form, function, or structure.
any process of formation or growth; development
a number or body of persons or animals migrating together.
no longer in existence; that has ended or died out
a well tested concept that explains a wide range of observations.
a diagram that shows how scientists think different groups of organisms are related.
A term used by paleontologists refer to the total number of fossils that have been discovered,
which the organism becomes better fitted to survive and multiply in its environment.
a class of individuals having some common characteristics or qualities; distinct sort or kind.
Fossils are the remains of plants or animals that lived a long time ago or the evidence of them.