It is obvious that land use and climate change can alter an environment. We have seen this happen in the rain forests of Malaysia and South America. Drought and other extremes of weather and climate have affected our environment in regions around the world.
These changes, regardless of what has caused them, create a great challenge to many species, and if they fail to adapt or adjust their geographic distribution, they run the risk of becoming extinct. A new study by researchers from Linnaeus University in Kalmar, Sweden has found that a higher degree of individual variations among species and individuals can be beneficial, reports Phys.Org.
The accepted theory is that higher levels of genetic variation among individuals should promote ecological and evolutionary success. This is done by altering the frequency of particular alleles, one of two or more alternative forms of a gene that arise by mutation. Choosing the right alleles provides a survival benefit to the organism while the wrong choice produces a selective disadvantage.
Although this proposition has not been systematically evaluated, the research team used previous studies on the diversity of plants, animals, and bacteria to determine if the theory was supported by experimental and phylogeny-based comparative investigations. Lead author Professor Anders Forsman explained: “our review provides strong evidence that more variable populations are less vulnerable to environmental changes, show decreased fluctuations in population size, have superior establishment success, larger distribution ranges, and are less extinction prone, compared with less variable populations or species”.
An interesting finding in the research is that variation is more beneficial if the conditions are harsh. Co-author Dr. Lena Wennersten explained that in some of the experimental studies they reviewed, “the experiments indicate that the benefits of diversity are generally expressed more strongly under stressful than under benign conditions”.
While there were some variations, the research also discovered that the relationship linking benefits to diversity is more often linear rather than curvilinear, meaning that increasing or decreasing one benefit will cause an increasing or decreasing change in the diversity of a species.
This linear relationship is most relevant to conservation aimed at protection and restoration of biodiversity, the researchers say. The authors use the relationship that links diversity to population fitness as an example of how best conservation resources are allocated between competing needs.
The researchers concluded their review aligns well with the idea that there is strength in diversity. Anders Forsman concludes: “there is still ample opportunity for progress and new discoveries. We hope that our study will spur further interest in this rapidly growing and important area of research”.
This study was published in the online journal Ecography on August 6, 2015 under the title: “Inter-individual variation promotes ecological success of populations and species: evidence from experimental and comparative studies“
