Urbanization is like a modern form of massive, gradual migration of humans which may have already been affecting our evolution and biological diversity.
Half of the world's population are living in urban areas. This has reached to a point where it has significantly affected ecosystems in the area.
True enough, researchers at University of Washington found some evidence in the 1,600 cases around the world where plants and animals are learning to adapt.
Adaptation by plants and animals are exhibited with changes in body sizes, shifts in behavioral and reproduction patterns.
For instance, hawksbeard (Crepis sancta
) seeds have grown larger. Scientists speculated that the plant adapted to a greater chance for the seed to germinate in an abundantly concrete surroundings. Lighter seeds get blown away from the tree and get dropped on a concrete. Having heavier, bigger seeds will allow the seed to fall of directly on the soil below.
Evolutionary adaptation of animals is not only unique to urbanization but also to climate-related anomaly. In previous months, scientists reported that extreme temperatures have genetically altered animals to adapt
in the changing environment.
Professor Marina Alberti, the lead researcher of the study said, "We found that there is a clear urban signal of big change, and also greater - physical and biochemical - change in urbanising systems compared to natural or non-urban anthropogenic systems."
The scientists are surprised with the drastic adaptation. This confirms the belief that Earth has already reached the Anthropocene epoch, where human activities start to have global impact to the planet's geology and ecosystems.
The researchers reported the study
to Proceedings of the National Academy of Sciences
See: Concrete Jungles Absorb Greenhouse Gases Like Forests Do