
LOW - STAAR 2022 (9B) - use for quiz review
Two scientists studied patterns of evolution in the fossil record. Many species they analyzed showed periods of slow changes interrupted by a period of rapid change.
This pattern of periods of slow change interrupted by periods of rapid change with few, if any transitional fossils, best describes the theory of-
MED - STAAR 2023 (9B) - use for test review
Certain species of the coral-like sea organisms called bryozoans first appeared about 140 million years ago. They remained unchanged for the first 40 million years and then suddenly experienced rapid genetic change.
Which process would BEST account for the pattern of evolution of bryozoans?


