Birds’ Battle with Climate Change

Genotypes selected for early and late avian lay date differ in their phenotype, but not fitness, in the wild.Sci. Adv.9,eade6350(2023).DOI:10.1126/sciadv.ade6350

Global warming has led to many changes in the world. Some of these changes are happening to our ecosystems. An ecosystem includes all the organisms living in a certain area and the non-living environment (like climate, temperature and the atmosphere). Whether a species can survive these changes depends greatly on if they have a certain characteristic that allows them to adapt.

For example, some organisms rely on the temperature of their surroundings to learn certain information. This can include things like knowing when their food source will be the most abundant or knowing when to reproduce. If the temperature starts changing, the timings of these processes can disrupt organisms and their ecosystem.

Looking at the Great Tit - the time and date that they lay their eggs to correspond the hatching of their offspring with the time when caterpillars are the most abundant and they gather all this information from their surrounding temperature. If the temperature no longer corresponds with the time when caterpillars are most abundant, there is likely to be less resources available for the birds and their offspring. This mismatch in timing can lead to a decreasing population of Great Tits in the future. To combat this change the Great Tits would have to adapt to lay their eggs at an earlier time in order to make sure they have a good food source available for their population as it grows.

Many studies have attempted to predict how evolution will factor into the changing climate by looking at variations in the DNA that may lead to beneficial traits being shown in some organisms of that species. However, these observations can play out differently in the wild because of other factors. A beneficial trait that can help an organism adapt to changing temperatures may not be suited to other features of the environment. If these birds were to lay their eggs at an earlier date to once more match with the availability of their food source they may have more resources to survive, but things like cold temperatures could in turn reduce their chances of survival.

So, to understand the process of adaptation better in relation to Great Tits, researchers selected birds with extremely early and extremely late patterns of laying eggs and allowed them to reproduce in a controlled environment. They then placed these offspring in the wild in order to observe their ability to survive. Those offspring, whose parents laid their eggs early, showed a small variation from their wild counterparts. That is, they laid their eggs earlier but not by a significant amount. But, those offspring who had been laid later showed a great difference in the wilderness. They laid their own eggs much later than the other birds. So, it can be seen that it was a slower process for Great tits to adapt to an earlier lay date, however, climate change is happening rapidly. In this way, this study raises concerns about the ability of the Great Tit population to be able to adapt to the sudden changes providing a valuable insight into the disruption of ecosystems as a whole.

The study makes clear the challenges of evolution and the rapidly changing climate. While organisms may adapt, whether or not they can do this at a fast enough pace is an important factor to judge their survivability. Further research is required to better understand how species are coping with changes to their ecosystem and to look at multiple species to see the larger effect of climate change.

By Nyrika

Works Cited

Biology Dictionary. “Directional Selection - Definition and Examples | Biology Dictionary.” Biology Dictionary, 28 Apr. 2017, biologydictionary.net/directional-selection/. Accessed 3 Sept. 2023.

Ecology, Netherlands Institute of. “Researchers Evaluate How Birds Can Respond to Natural Selection to Keep Pace with Climate Change.” Phys.org, 30 June 2023, phys.org/news/2023-06-birds-natural-pace-climate.html. Accessed 3 Sept. 2023.

Murray, Melissa. “What Is an Ecosystem?” The Australian Museum, 7 Nov. 2018, australian.museum/learn/species-identification/ask-an-expert/what-is-an-ecosystem/. Accessed 3 Sept. 2023.