Twisted and tangled buildings, charred landscapes and desperate people fleeing with only the clothes on their backs are typical scenes in a war zone.
But these images don't tell the full story, says Kiyoko Gotanda.
"When we think about the devastation of war, we don't very often think about the ecological fallouts and the consequences war has on wildlife's future development," she says.
The Brock University Assistant Professor of Biological Sciences is part of an international team that reviewed and integrated existing research on the impacts of war, religion and politics on urban evolutionary biology.
Gotanda's expertise is in how biodiversity the variety of animals, plants, fungi, bacteria and other life forms found in a particular ecosystem evolves and is maintained through natural selection and adaptation.
Central to selection and adaptation is genetic variation and how genes are passed on to ensure the survival and reproduction of populations of organisms.
As part of the international review, Gotanda examined how armed conflict affects the movement and genetic patterns of wildlife in cities.
Examples featured in the study include:
- The increase in the number of tuskless African elephants (Loxodonta africana) related to intense poaching that occurred during Mozambique's 20-year civil war.
- The return of Asiatic black bears (Ursus thibetanus), amur leopards (Panthera pardus orientalis) and yellow-throated martens (Martes flavigula) to the demilitarized zone set up between North and South Korea.
Gotanda says she had a few revelations about ecology and war during the project.
"The one that really stood out for me was what civilians have to do to survive war," she says. "The ecological and evolutionary consequences of cutting down trees for fuel or scavenging what they can just to stay alive is not something I had thought about."
The study looks at habitat loss in Sarajevo, for example, where three-quarters of all urban trees within the siege line around the city were felled for firewood during the Bosnian War.
Gotanda says habitat loss can impede gene flow in animals and plants. Gene flow is the movement of genetic material from one population to another, which can increase genetic variation.
Humans can also induce gene-flow by introducing gene varieties to an ecosystem. The discovery of sand dropseed (Sporobolus cryptandrus) in Luhansk, Ukraine in 2014, for example, was attributed to the start of Russian aggression in the region. This invasive species then took hold in the ecosystem, diverting valuable resources away from native species in nearby environments, she says.
Scavenging can also cause disruptions in ecosystems. The study highlights the example of famine experienced by local communities caught up in the Democratic Republic of the Congo's civil war, which resulted in a five-fold increase of primates being hunted for food.
These and other examples of the impacts of war, along with religion and politics, are found in "Legacy effects of religion, politics and war on urban evolutionary biology," published July 2 in the journal Nature Cities.
Washington University postdoctoral fellow Elizabeth Carlen with University of Manitoba Associate Professor Colin Garroway and University of Warsaw Professor Marta Szulkin led the 36-member international team, which reviewed a wide range of studies about how human actions arising from war, religious practices and political decisions affect the environment and evolutionary processes of wild animals and plants in city settings.
Overall, Gotanda says the study broadens the view of how human actions affect city environments.
"When we talk about urban ecology and urban evolutionary biology, we often think of squirrels, pigeons, raccoons and maybe the park down the road," she says. "This paper shows a reality most people don't think about, mainly, what we humans value or don't value has a strong effect on all of urban ecology and evolution."
