All of the above points are valid for fossils' contributions in understanding the process of evolution. They allow us to study the ancestry, we can see the homologous organs or structures, if fossils are well-preserved; different fossils can lead us to follow the cycles of the changes that occurred during macroevolutions, and fossils can be used to study different populations which had different body structures for surviving in different environmental conditions.
Parenteral route
injecting a drug into the body, includes intradermal, SQ, IM, IV routes. Drugs given IV route produce the most rapid actions because they are given directly into the bloodstream.
About 7 years hope I helped :)
They can harm other native species and thrive in the new environment which can potentially make the other species go extinct as the new species has no predators.