Difference between cycad and fern

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

The frequency of alleles in a population that is in hardy weinberg equilibrium? a . changes in each successive generation b. is less important than the frequency genotypes c. shows evidence of the process of natural selection d. remains the same over several generations

How do you think earths interior affects what is happening on the surface? 2. how do fossils support the continental drift hypothesis? 3. how does sea- floor spreading support the hypothesis of continental drift? 4.what do scientists observe when they studied the magnetic fields of rocks on the sides of mid-ocean ridges? 5. what is a tectonic plate ? 6. explain mantle convection 7.how can movements of the continents affect earths climate? 8. what occurs during drifting?