Without a doubt, we humans are changing the natural environment. Because of our activities, we are now experiencing melting glaciers; rising sea levels; ocean heating; and more frequent and more intense droughts, heat waves and storms – all the result of man-made climate change. These effects create chaos on people’s communities and livelihoods.
But how do wild animals react to these changes? Finding the answer to that question has been a complicated process and it is still unclear.
But now scientists have discovered significant differences in the brains of animals with two different personality types: those who act fearlessly and those who seem afraid of new things. On the one hand, being fearless can help wildlife, especially birds, explore new nesting areas, find new food sources, and help them adapt to changes in their environments. But on the other hand, being scared also has an advantage. It can help protect them from dangerous new things in their environments, such as cars.
With the pace of climate change, however can be brave win. In fact, a research team of researchers from Africa, Europe and North America concluded that animals’ ability to respond to climate change probably depends on how well they change their habitats, such as caves and nests.
One fear-flexible bunch
To assess what causes some animals to fear change and others to embrace it, researchers who have published their report in the scientific journal have. PLOS ET on May 10, 2022, compared six wild females sparrow: three of them acted fearlessly and three who seemed afraid to approach a new object at their feeding trough. The new items were a red keychain with wrist spool wrapped around the dish; a white plastic cover over a portion of the dish; a green, plastic Easter egg placed on top of the food in the center of the dish; a normal, silver-colored dish painted red on the outside; and a flashing light hung above and aimed at the front of the dish. The fearless birds fed at the dish regardless of the presence of the new objects, while the fearful birds avoided the dish when the unknown objects were in sight.
Several weeks after this behavioral test, researchers examined gene expression in four brain regions of the sparrows. When wild animals are introduced to something new in their environment, the genes in their brains respond and help them process the information, compare it with experiences, and decide whether to approach or avoid a new object.
The researchers found that three out of the four areas of the brain examined showed differences. For example, the genes expressed in hippocampi in the fearless birds were different from the genes in the fearless birds. The hippocampus is associated with decision making, learning, memory and spatial navigation. There were many more dopamine D2 receptor transcripts – which are associated with boldness and exploration – present in the hippocampi of the fearless birds. In contrast, birds that avoided new objects had multiple transcripts for the estrogen receptor beta gene, which have been linked to anxiety.
Since social creatures, such as sparrows, can learn from each other, a mixture of both personality types in a herd may be part of the reason why this species has had such great success in human-changing environments.
Of course the fear of new things, or neophobia, is a problem that people also struggle with. Therefore, the neurobiological gene receptors that the researchers identified in the sparrows could help other researchers develop drugs to target anxiety in our own species.
Two brave strategies for maneuvering climate change: Using microclimates and relocation
For non-human animals, it may become extremely important in the near future to have a tendency to try new things – or to act fearlessly.
Birds build nests to keep eggs and hatching chicks warm in cool weather, but they also need to make adjustments in a nest’s insulation to keep the chicks cool in very hot conditions. Mammals, such as groundhogs and rabbits, go to sleep or sleep in underground caves that provide stable, moderate temperatures to avoid the above-ground conditions, which are often far more extreme.
In a paper with the title Extended Phenotypes: Buffers or Amplifiers of Climate Change ?, which was published on June 16, 2021 in the journal Trends in ecology and evolution, researchers reported that they found that an animal’s ability to respond to climate change probably depends on how well it can change its habitat; in other words, an animal must be able to fearlessly cope with environmental changes.
This study examined extended phenotypes, which are changes that organisms – such as birds, insects and mammals – make in their habitats. An extended phenotype can range from just a hole in the ground occupied by an animal to leaves rolled into cavities by insects; and from nests of all shapes and sizes built by birds and mammals to bicolonies and termite mounds. These extended phenotypes are important because they filter the climate into local sets of conditions immediately around the organism, or what biologists call microclimates.
Because extended phenotypes are constructed structures, they are often modified in response to local climate variations and potentially in response to climate change. This process is called “the plasticity of the extended phenotype.” An example could be a bird’s nest that is well insulated to protect eggs or young birds from the cold. So when the temperatures get warmer, if the bird does not adjust the insulation in the nest, it can cause the chicks to overheat. As another example, termites build mounds that capture solar energy and wind, driving the airflow through the colony, stabilizing oxygen levels, relative humidity, and temperature in the mound.
But the idea of microclimate is broader than just constructed habitats. Microclimates typically differ significantly from nearby climates, which means that the weather conditions in an area can provide some information about what animals experience in their microhabitats.
For example, even if a weather station can tell you that the temperature in Bozeman, Montana, is 90 degrees Fahrenheit, simply by moving from the south to the north side of a building, you can experience microclimates that are strikingly different and often not trapped. of the weather data.
The same goes for animals of many different sizes: a moose can move from an open, ash landscape to a shady river corridor to cool off; a snake can move from its underground hole to a sunny rock to warm up; and a small insect flying between the top and bottom of a leaf can experience temperature differences of more than 20 degrees Fahrenheit.
So animals that are not afraid to move – and thus use microclimates to their advantage – or to make changes in how they build their structures – such as caves, mounds and nests – will take advantage at home in light of the increasing effects of climate change.
Three keys to future success: fearlessness, flexibility and phenotypes
Worldwide, rising levels of carbon dioxide in the Earth’s atmosphere causes temperatures to rise and precipitation patterns to shift. For biologists, a key issue is understanding the current effects of climate change on species and predicting the future, including how wildlife areas may change and what risk of extinction is for different animals.
According to a report published in the scientific journal Nature communication on July 23, 2019, animals are now unable to keep up with the pace of climate change.
Let’s hope they find and use their fearlessness and flexibility in their extended phenotypes to help them gain ground.
Here is to find your true places and natural habitats,