Hobbies And Interests
Breeding
With temperatures in the spring, when many animals normally reproduce, becoming ever warmer, some animals have been observed to be breeding earlier in the year. Canadian red squirrels and several bird species now mate when the temperature suits them, rather than waiting for a specific time of year, as they have done previously. Canadian squirrels have found this very beneficial, as there are more mature squirrels to collect nuts and pinecones before they hibernate.
Migration
Many bird and mammal species migrate each year to warmer temperatures during the winter. This is due in part to the temperature, but mainly in the pursuit of food. With temperatures staying higher for longer, migratory patterns have changed wildly, as animals no longer have to deal with frozen water sources and leafless plants. In the longer term, this could also lead to a change in tactics by the predators of these animals.
Food Sources
Animals will also have to deal with the negative effects of global warming, like the reduction in plant life, as water sources and rainfall disperse. This means animals will have to adapt to deal with other food sources. During Darwin's studies, he discovered that finches evolved different shaped beaks, so they could access what food was available in the local environment. This has also been noted in other animal species, and may happen again as natural food sources disappear due to global warming. This could also be noted among predatory animals, as common prey die out due to lack of vegetation.
Hibernation
Many mammals, such as bears, hibernate over the winter so as not to have to cope with the freezing conditions. With temperatures during these winter months increasing, these animals may have shorter hibernation periods, as winters come later and spring starts earlier. This pattern has already been noted among migratory birds that commonly flew south for the winter, but now stay north during the early winter.
Plants
Although not as commonly noted as evolution in animals, plants also change to adapt to different conditions. Cacti, for example, have developed traits to help them live in hot dry conditions in the form of hybrid photosynthesis. With deserts expanding, other plants may also develop the deep roots and small leaves associated with plants in arid conditions. Higher carbon dioxide levels in the atmosphere may also have an effect. Plants need carbon dioxide to grow, and in high carbon environments plants grow to a greater size. A study of milkweed by the University of Michigan noted that increase levels of carbon dioxide commonly reduced the chemical defenses a plant has against predators, so the plants developed physical resistance in the form of tougher leaves.
Extinction
Global warming has negative effects on the animal and plant world, and can lead to extinction of certain species. While this in itself is not a good thing, it too may lead to evolution. Predators will start to hunt different animals, which in turn will evolve new defenses; reduction in water sources may see animals change to require less water; and falling plant diversity could see herbivores choose different food sources.
Sea Creatures
The majority of studies on the effects of global warming on animals and plants have been conducted above ground, but there is no reason to think this may not occur in the seas as well. Many fish migrate to warmer waters, which may not be necessary if sea temperatures remain high, and the same effects seen on breeding patterns may also occur. Plants in the seas will also have to deal with increased carbon dioxide, and may evolve in a similar way to the milkweed.