A study on Brazilian rain forests states that deforestation has accelerated the process of evolution.
Deforestation is a major issue that has given rise to serious concerns globally and many studies have been conducted on the same. In one such study of the Brazilian rain forest, researchers from Sao Paulo State University, Brazil, found that deforestation has accelerated the process of evolution.
In areas where populations of large-billed, fruit-eating birds have disappeared due to loss of their habitat to deforestation, palm trees have evolved to produce smaller and less successful seeds.
Palm trees depend on these large birds for dispersing their seeds. These large fruit-eating birds eat the fruit and then drop the seeds off in faraway places. Scientists state that fruits that fall near the palm tree fail to grow successfully. Also, fruit dropped with pulp intact (which is usually the case when smaller birds eat the fruit) fail to sprout.
Researchers found that it would take approximately 100 years to produce the measured changes in seed size for successful germination without the presence of large, fruit eating birds.
During the research, scientists were able to collect over 9,000 palm seeds from areas in rain forests that were fragmented into coffee and sugarcane plantation during the 1800s. The scientists then used evolutionary tools to correlate these small seeds with the absence of large birds, which in turn is correlated to the success rate of germination of these seeds.
"Unfortunately, the effect we document in our work is probably not an isolated case," said Mauro Galetti from Sao Paulo State University in Sao Paulo, Brazil, who led the international research team.
The study is published in the journal Science.
