
It may be time to hit the road in pursuit of scientific research. Millions of animals are struck by vehicles every year and killed as a result. These accidents have even pushed some species to extinction. While roadkill is never pleasant, the animals could bring an opportunity to conduct scientific research more ethically.
Road to discovery
Roadkill could be a “valuable source of animals for study that does not require and could even replace the use of live wildlife,” said a study published in the journal Biology Letters. Researchers identified approximately 117 different uses for roadkill across various scientific projects. “We found examples of successfully using roadkill to map species distributions, monitor disease and environmental pollution, study diets, track invasive species, supply museum collections and even discover species previously unknown to science,” said Christa Beckmann, the lead author of the study, in a statement.
One of the most common uses for roadkill is to identify and determine the populations of species in an area. Many species are “hard to see,” Beckmann said to Science. “You don’t just trip across them as you’re walking. So finding dead animals on the road might actually be an easier way to quantify the presence of these animals in the habitat.” Several lizard and rodent species were “first discovered as roadkill, while deer carcasses have been used as bait to attract eagles at the center of research,” said AAP. In another case, a “paleontologist took photographs of animals’ remains as they were repeatedly run over to teach students about the process of fossilization.”
The road less traveled
A big advantage of using roadkill for research is that it is “highly ethical,” said the study. It could be used as an alternative to invasive sampling methods. “If you want to take a genetic sample, you don’t need to trap live animals or handle them, both of which can cause stress,” said Beckmann. “You can just drive along the road and use samples of roadkill.” It aligns with the global guidelines for animal research known as the 3Rs: refinement, replacement and reduction. These tenets aim to reduce the number of animals needed for research, along with reducing suffering and protecting population numbers.
Researchers still need permits to collect and handle dead animals from the road because of potential biohazard and traffic risks. The animals can “harbor disease that is transmissible to humans,” which requires protective gear, said the study. In addition, it could be dangerous to collect the animals and “necessary precautions should be taken when collecting roadkill on and around roads and highways, such as wearing reflective clothing and being mindful of traffic.”
In a car-centric society, roadkill is an unfortunate side effect. Some species are even being “driven toward extinction because of traffic,” said Scientific American. “Vehicles continue to be overlooked environmental forces that are likely to decimate more and more animal populations.” Despite this, “using these losses wisely could help drive scientific discovery and conservation forward, rather than letting valuable information decompose by the roadside,” said Beckmann.
We can learn from animals without trapping and capturing them



