A huge advancement in the study of elusive species? DNA testing the evidence they leave behind — whether that’s poop, saliva or blood snacked on by hungry mosquitoes — says primatologist Todd Disotell. The scientist has worked for years on the study of mysterious species of gorillas, he explains at TEDxNYU, a study that for many years felt like a huge game of cat and mouse.
From his talk:
“For the first decade that [we knew about the Cross River gorilla] Gorilla gorilla diehli, we had one fuzzy picture of it running into the forest,” Disotell says. “It took many, many years to get clear pictures of these [animals], so that we really knew what they were like…
To try to figure out, ‘How many are there?’ we would go around and count the nests. Gorillas, every night when they go to sleep, they make a nest, so if you wander around the forest and you find a group of nests, you can count how many nests there are and get a rough estimate of how many gorillas are in that population … Unfortunately, sometimes, two of them will sleep in the same nest or they’ll wake up grumpy and make a new nest, so just counting nests isn’t good enough… [But] one nice thing in particular about gorillas is they eat a very strong fiber diet, and so almost 99% of the time when a gorilla wakes up in the morning, they leave a DNA sample behind for us.
And so by going out in force with our little pooper-scoopers and scooping up samples, we can count the number of unique individuals there, we can figure out their relationships. We can see that the male Silverback has fathered all of the offspring; we can see if the females are related to each other or if there are other relations.
DNA fingerprinting the smelly leavings of these notoriously mysterious creatures gives researchers an in-depth look into gorilla life, Disotell says, and analysis of other biological material, from blood culled from local insects to saliva left on a plant, provides huge clues to better understanding the full scope of wildlife in any given area, providing great fodder for the possibility of making new discoveries in biology by unearthing evidence of organisms yet to be seen.
Watch his talk below for more on how DNA tracking is transforming wildlife studies and conservation: