Answer:
Europeans arriving in the new world, unintentionally brought invasive species that destroyed some land in the new world. The Europeans carried some diseases that Eurpoeans were resistant to, but the Natives were not since they had no prior contact to those those types of diseases such as smallpox, measles etc etc.. Invasive plants, animals, viruses carried from continent to continent unintentionally because the population at the time simply did not know. and this went vise versa, but natives and the new world land was impacted the most.