| While most 31st-century humans agree that the last thousand years have been pretty good to the species, and to the various environments found in Sol System, there have been some bitter, bitter disputes. Humanity needed space, and so did the many diverse species of earth, and by terraforming Mars, Venus, Europa, and Luna, new habitats and ecosystems were created. Unfortunately, a few alien ones were destroyed. Granted, there wasn't much life there to begin with, and none of it was intelligent (at least not intelligent enough to file a formal complaint with the UN Council on Terraforming), but the ecologists still argued that we had no right to do what we did.
The reintroduction of species to the overall gene-pool was also a matter of dispute. Kids were happy to see dinosaurs and wooly mammoths at long last, and the dodo's return to the dinner plate was welcome, but again, there were those who argued that no matter what the overall public good, messing around with nature is wrong. Entire political parties rose to power on the basis of their convincing arguments surrounding the issues of terraforming, habitatification, de-extinction, and specie-tweaking.
The one thing everyone agreed on, however, was that genetically granting sapience to african elephants was a mistake.
Sol System is the birthplace of all Terran species. With five inhabitable planets, it is easily the densest population of humanity in the galaxy.