the 6th major extinction

Humans may cause the sixth major extinction. Biologists estimate that the extinction rate for species is 100 to 1,000 times greater than normal "background" extinction due to human interference. Humans impact species in numerous ways. This includes spreading diseases, destroying habitats, hunting animals to extinction or introducing alien species into new environments. Harvard biologist Edward O. Wilson estimated that as many as 30,000 species go extinct every year.

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what is microevolution?

Microevolution is simply a change in gene frequency within a population. Evolution at this scale can be observed over short periods of time — for example, between one generation and the next, the frequency of a gene for pesticide resistance in a population of crop pests increases. Such a change might come about because natural selection favored the gene, because the population received new immigrants carrying the gene, because some nonresistant genes mutated to the resistant version, or because of random genetic drift from one generation to the next.

why is fossil record hard to interpret?

 Ffossil is hard to interpret because the animals' or plants' are at least 10,000 years ago, so it is very hard to tell the shape or species or the animals' or plants' fossils.  In addition, the paleontologists always break the fossils to take the main shape out, so a lot of fossils do not have enough parts on them.  Getting a fossil also is hard since the paleontologists are getting the fossils under the heating sun and inside the ground.  On the other hand, interpreting the fossils also can become easier because some ants are helpers who collect the tiny pieces of fossils under the ground.  To sum up these reasons, interpreting the fossils is a hard job, and we need to appreciate the hard works of the paleontologists.