By Tina Whitaker
“Biodiversity is the totality of all inherited variation in the life forms of Earth, of which we are one species. We study and save it to our great benefit. We ignore and degrade it to our great peril.” —E.O. Wilson
I’ve heard many scientists attribute their passion for science to experiencing a sense of awe in nature. Whether they grew up hunting, birding, going to the beach, or climbing mountains, that sense of awe kept them coming back for more. They were hooked on nature. For many, that sense of awe comes from the shear diversity of life that has evolved, including six kingdoms and an estimated 5±3 million species and counting (Costello et al. 2013). As we race through the 6th mass extinction, the concern for our loss of species has come to the forethought of anyone who understands the importance of biodiversity on our planet.
Biological diversity, or biodiversity, is a term that was coined by E.O. Wilson in his book, titled Biodiversity. At the most basic level, biodiversity is the vast variation of life, but biodiversity can occur at different levels: ecosystem, community, species, population, organism, and gene. Most researchers focus on genetic, species, and ecosystem diversity.
From the human perspective, we can put value on biodiversity by considering how biodiversity directly benefits humans. Just like any other animal on the planet, we rely on our environment and its resources for survival: food, water, shelter, etc. Many potential resources, including medicines have yet to be discovered. If we alter the environment, we alter those resources. Habitat destruction and fragmentation have caused homogenization of some habitats. For instance, bottom trawling of the continental shelf has caused a decrease in biodiversity of the seafloor (Thrush et al. 2006), ultimately impacting future seafood resources.
There is also an ethical component to conserving biodiversity. Aldo Leopold, who championed the concept of the “land ethic” in his book, The Sand County Almanac, explained that one must remove herself from the center of the universe, and understand that humans are part of the ecosystem. By understanding our role, and our connection to the land, we develop an ethic to conserve the integrity of the system, regardless of the resources that it provides. However, fostering that connection is becoming ever more difficult in a world where we walk along concrete sidewalks, purchase food in brightly colored packages, and spend the majority of our time in front of computer and TV screens.
Since it may be difficult for people to connect with nature, quantifying biodiversity and its importance has become a major theme in conservation research. A review of experimental studies has shown that retaining a functional marine system requires high levels of biodiversity (Gamfeldt et al. 2014). Due to a variety of anthropogenic impacts, including overharvest, invasive species, ocean warming and acidification, and habitat degradation, marine ecosystems are currently experiencing rapid loss of and changes in biodiversity. As biodiversity decreasing, the productivity of our oceans also decreases (Gamfeldt et al. 2014). A change in the number of species in an ecosystem can change how nutrients are cycled through the system (Cardinale et al. 2012), which can be heavily impacted by alterations to predator diversity (Griffin and Silliman 2011). Additionally, removal of the diversity of ecosystem engineers, the species that create, modify or maintain a specific habitat, which creates niches for other species, can cause a spiraling loss in diversity. When analyzed across ecosystems and when multiple functions within an ecosystem are incorporated, the impacts of biodiversity loss to ecosystem functioning are even more devastating (Lefcheck et al. 2015).
Overharvest has led to a decline in the genetic diversity of many marine species (Pinsky and Palumbi 2014). Decreased genetic diversity can be detrimental to a population because it can lead to a loss of evolutionary potential and the ability to adapt to future environmental changes (Ryman et al. 1995; Allendorf et al. 2008). However, in marine populations specifically, levels of biodiversity and genetic diversity are still not fully understood because it can be difficult to obtain precise measures of population size in the world’s vast oceans, and some cryptic species are nearly impossible to sample. As technology improves, researchers are delving into the depths of our oceans in an attempt to quantify the true levels of marine biodiversity. A component to this quantification is to perform baseline surveys and establish phylogenetic, genetic, and epigenetic patterns of marine species.
Stay tuned to the Janosik Lab blog to learn how we are contributing to the conservation of marine biodiversity by examining settlement on artificial reefs in the Gulf of Mexico!
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Cardinale, Bradley J., et al. "Biodiversity loss and its impact on humanity." Nature 486.7401 (2012): 59-67.
Costello, M.J., May, R.M. and Stork, N.E., 2013. Can we name Earth's species before they go extinct? Science, 339(6118), pp.413-416.
Gamfeldt, Lars, et al. "Marine biodiversity and ecosystem functioning: what's known and what's next?." Oikos 124.3 (2015): 252-265.
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