DinoCal - Priyanka Davechand
Priyanka Davechand: Geochemist, Dinosaur Dentist. PhD candidate at Wits University, Bridge the Gap Geosciences Mentor. #isotopes #calcium #dinosaur #teeth #enamel
Her Research: When you look at a predator like, for example, a grizzly bear, huge and terrifying with sharp teeth, you might think that they only eat meat, you probably are also thinking other things, like run!, but if pushed to answer what it eats, meat would high on the list. But scientists know that they eat all sorts of things, including grasses, insects, potato-like tubers, fish and more. They will eat pretty much anything that they can get their gigantic paws on that has some nutrition. Another name for this is an omnivore, like most people. But what about dinosaurs? Which dinosaurs were meat eaters, which were plant eaters, and which were omnivores? We can’t study them but we do have their fossils.
Priyanka Davechand is figuring this out with fossil dinosaur teeth found in Southern Africa. The trick is in the food that these dinosaurs ate millions of years ago and what they did with the nutrients in them. One thing about teeth, and bones, is that they have a lot of calcium in them. Animals get calcium from the food that they eat and incorporate it into their bones and teeth. But not all calcium is the same. There are a few different forms of the calcium atom, Calcium-44 and Calcium-42 are the two we care about for this. They are different by two neutrons which don’t fundamentally change them, but it does change where they are found in the food chain. Plant eaters have more Calcium-44 while carnivores have more Calcium-42.
Priyanka is able to take the smallest of samples from fossil teeth and then pull those calcium atoms out of the fossil. This is where her science superpowers come into play. She uses ion extraction technology to pull out the calcium ions and then uses mass spectrometry to separate the Calcium-42 from the Calcium-44 and measure them. To be able to measure the weights of individual atoms is so amazing when you think about it. With this information she’s then able to say with some certainty what different dinosaurs ate and maybe, as she says, who was on the menu!
Her Science Spark: “As a young child, I was always curious. Many of my early 'science' memories are those shared with my sister. As kids, we would mix all sorts of things together and pretend to be crazy scientists in a lab. I always wanted to know the why’s and how’s about different things. I loved to watch my mother mix ingredients in the kitchen and on family trips, my dad would always talk about the different geographical features.”
Her Heroes: “My family & people who make a positive change:
Her Top Tip: “Anything is possible if you put your mind to it. If you are passionate about science, go for it! Anyone can succeed, especially if you are passionate. What is meant to happen, will happen.”
Who Can be a Scientist: “There were many times I felt like I didn't have what it takes to be a scientist. I felt like I didn't know as much as I should. But what does it take to be a scientist? For me, it is curiosity and that is the first step. You need to be willing to learn and to put in the hard work. No one is born knowing everything. In life, we live, grow and learn. If you are determined and willing to learn, you will succeed. Things happen for a reason so never be discouraged, it is all part of the process.”
Her Rank Order of What You Need to Succeed: Curiosity, hard work, communication, creativity
What Else do You Need? Resilience, be open-minded and dedication
Her Superpowers: Ion extraction, the power to separate ions (charged atoms) from different objects. Mass spectrometry, the power to separate atoms from each other based on their weight and determine what atoms, and what isotopes are present.
Scientists are People Too: “I love dogs and watching movies. I love to garden and appreciate the beauty of nature.”
Connect: LinkedIn
Funded by Genus Palaeosciences, a National Research Foundation and Department of Science and Innovation Centre of Excellence at Wits University
