Rising temperatures might also affect our sea turtles. The upper-temperature limit of the sand on the beach for the eggs to incubate is 34 degrees Celsius. The temperature during incubation determines the sex of the sea turtles. With rising temperatures, the temperature of the sands could become much higher and also would lead to higher number of females being produced.
Most animals on earth are cold-blooded, which means having a body temperature that varies with that of their surroundings. These cold-blooded animals are the ones that warmer temperatures are affecting the most. A one-degree rise Celsius has resulted in about a 10% increase in metabolism, which resulted in smaller tortoises and smaller lizards. In the photo above, the two frogs are both adults of the same species collected from the top of Mt. Kinabalu in Malaysia; however, the one on the left was collected in the 1980’s, and the one on the right was collected in 2008.
Even when cold-blooded animals are inactive, they consume more energy. If the temperature rises 6 degrees C by 2100 as predicted, the reptiles and amphibians will need to eat about 75% more food to keep their present size. For the Komodo dragon, that would mean that they would need to catch 200 more chickens per year!
Some animals are shrinking more than others, which is a problem. For example, if a predator doesn’t shrink as much as its prey, the predator would either have to catch more prey or change its size, or it will probably die out. Dr. Andrew Hirst, co-author of a study published in The American Naturalist has said, "The consequences are that at warmer temperatures a species grows faster but matures even faster still, resulting in them achieving a smaller adult size. Decoupling of these rates could have important consequences for individual species and ecosystems."
Also, animals that live in warmer climates tend to have larger limbs to be able to release the extra heat that they have. A study showed that four species of parrot’s bills in Australia from 1871 to 2008 have become 10% larger. They adapted to the warmer climates to be able to release the extra heat.
The speed of the current global warming event is happening a lot quicker than it did in past warming events on our planet. This might mean that animals might not adapt quick enough. The Intergovernmental Panel on Climate Change estimates that 20 to 30 percent of assessed animals could be at risk of extinction if average global temperatures reach projected levels by 2100. The evolution of the animals to adapt would have to happen 10,000 times faster than the current rate to avoid extinction.
Scientists will need study further to see how animals in all parts of the food chain will be affected by warmer temperatures. Approximately one billion people rely on fish as their main protein source. Warmer water holds less oxygen than cooler water. With warmer un-oxygenated water, it makes it hard for the big fish to get enough oxygen, which might result in them not growing. With some smaller fish, we might need more fish to feed people. So the evolving body size of animals might affect humans.
Usually, we think of climate change affecting the distribution of the fish. But, this is kind of a surprise where climate change has an effect on the size of animals! #bodysizeofanimals #globalwarming #smallerfish