Rainfall collects in a crack in a rock. When the temperature drops, this water freezes and expands. This causes the crack to become slightly larger is this weathering or erosion

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

Name the following: (a) category of pathogen that causes diseases, like common cold and mumps. (b) the microorganism that requires a host to produce.

Asmall number of finches are removed randomly from the wild and placed in a protected bird area. they are given as much food as they need and have plenty of space. why would natural selection not occur in this population? a. there is no reason for genetic mutation to occur. b. the birds compete for limited resources, c. the population has not reached carrying capacity. d. there is no genetic variation in the finches.