Final answer:
Later fall frosts and the northward migration of tree and plant species suggest global climate change, disrupt seasonal behaviors of species, and force both latitudinal and elevational migrations which can lead to ecological and population changes.
Step-by-step explanation:
Later fall frosts and the northward migration of some tree and plant species may indicate signs of global climate change. This phenomenon is a response to the increase in average global temperatures that triggers a shift in the ecosystems and the habitats of various species.
For instance, butterflies and amphibians are showing earlier seasonal behavior in the United Kingdom, which could impact their populations. Earlier emergence and mating might not coincide with other environmental cues and food availability.
Similarly, many flowering plants are blooming earlier, which raises the concern of what occurs if their insect pollinators are not present at the same time, potentially leading to a mismatch in the pollination process and negatively affecting plant reproduction.
Additionally, introduced species like the emerald ash borer are benefiting from milder winters, causing higher mortality in ash trees. Moreover, native species like the Hawaiian honeycreepers face a diminishing safe habitat because the warmer climate allows mosquitoes carrying bird malaria to survive at higher altitudes.
Global warming is not only causing species to move latitudinally but also forces tropical species to move to higher elevations, which might not be sustainable due to the lack of a 'species pool' at those elevations.