Humans affect the environment and animals significantly - and more than we think. They actually play a very significant role on evolution, as revealed in a new study released in January 2.
According to a report from Phys Org, the study was spearheaded by the University of Washington and published in the Proceedings of the National Academy of Sciences. The researchers studied 1,600 instances of phenotypic change, which is known as the modifications in the creature's observable traits including size, development and behavior. These samples come from a range of different regions and ecosystem all over th world, which were then organized in a geo-referenced database in an attempt to classify human-caused signals from natural baselines and non-urban drivers.
"We found a clear urban signal of phenotypic change - and greater phenotypic change in urbanizing systems compared to natural and non-urban anthropogenic, or human-created systems," lead author Marina Alberti said. She is also the professor of urban design and planning, and the director of the Urban Ecology Research Lab in the University of Washington College of Built Environments. "By explicitly linking urban development to heritable traits that affect ecosystem function, we can begin to map the implications of human-induced trait changes for ecological and human well-being."
Some of the effects of human-caused urban disturbances are the acidification and pollution of bodies of water, relocation of species, heat, long-term harvesting of medicinal plants and even changes on the avian reproductive patterns.
Alberti explained, "The significance of these changes is that they affect the functioning of ecosystems. They may inhibit the ability of seeds to disperse, cause exposure to infectious diseases, or even change the migratory patterns of some species."
Of course, not all evolutionary moves of species have been to their detriment. Co-author John Marzluff, professor of environmental and forest sciences, added that there are creatures who are adapting the traits to continue living in a changing world.
"Certainly many species have been, and will continue to be, extinguished by human action, but we reveal how others are evolving the necessary strategies and physical characteristics to coexist with humanity," he said.
A report from New York Times last December revealed one of the species that rapidly evolved to save itself from the dangers of pollution: killifish in the Lower Passaic River and Newark Bay. This site, a highly polluted area where toxic chemicals leak to, are still home to some marine lifeforms - and a study published in Science Magazine revealed that certain populations of killifish were able to develop genetic adaptations to survive in these human-affected environments.