Sarah Lacy really likes a “good brow ridge.” She thinks “it’s hot!”
In class, Lacy, a new assistant professor of anthropology at California State University, Dominguez Hills (CSUDH), and her anthropology students call that facial characteristic a “supraorbital torus,” which was sported by Neandertals around 40,000 years ago. They have also given the long-extinct human species a “sexy” social media presence with Lacy posing with their skulls in a series she calls “Hot Hominin of the Day.”
“I dress a bit unusual, and my students were joking about it. They thought I should create an ‘Outfit of the Day’ blog. It seemed a little frivolous, so I came up with a way to have fun with that idea, but use the posts as outreach to draw attention to our program,” said Lacy, who jokes that between Homo Sapiens and Neandertals, the latter are “much more attractive.”
Lacy arrived at CSUDH in fall 2017 from the University of Missouri-St. Louis, where she taught biological anthropology for three years. She earned a Ph.D. in biological anthropology at Washington University, and performed her post-doctorate research at Durham University in England, where she is now an honorary research fellow. Her doctoral work focused on oral pathology and health in Neandertals and early modern humans in the Late Pleistocene in Europe and Southwest Asia.
Archeology has been a fascination for Lacy since she was four 4 years old. As she grew, her interest turned more toward Egyptology, but kept evolving over time.
“As an undergrad, I had an amazing adviser, Trenton Holliday, who worked on Neandertals and was really invested in his students. I was interested more in Homo erectus when I started grad school, but because he was working on Neanderthals, I started really getting into it,” said Lacy, who has traveled extensively in Europe and in Kenya to X-ray fossils and conduct her research.
“The sample sizes in Europe where much larger than those in Kenya, so I was able to back pack across Europe for four months with the X-ray machine just going from museum to museum collecting data,” she added. “What was also great about Europe was in the evening I was able to go to a bistro, instead of just going to sleep in a tent.”
Neandertals are modern humans’ (Homo sapiens) closest extinct relative, and one of about two dozen species of hominins, or Hominidae, which consists of all species of the last common ancestor of living apes going back approximately 7 million years.
In 2010, a study was published showing that Neanderthal DNA was found in modern humans in Europe and Asia, providing the most concrete evidence that migrating humans interbred with Neandertals after leaving Africa.
“When that paper was published I felt vindicated. I was always a big proponent that we probably bred Neandertals out of existence because every time humans come into contact with other humans, they start having sex, especially back then with such low population densities,” Lacy explained. “Regarding species trying to kill each other off; there was probably not a lot of incentive for being that aggressive. It would have been too dangerous.”
Lacy’s more specific interest and research on Neandertals and ancient human species focuses on periodontal disease and examining cavities, tooth loss, and other unusual pathology, such as hypercementosis, when the roots of the teeth swell in response to excessive “loading forces” over time from chewing.
“The mouth is a good microcosm of overall health, and teeth preserve very well in the fossil record,” said Lacy, who has published several papers and chapters in journals about her research. “I was looking at it with an ecological competition perspective, with the ultimate question as to why Neandertals are not here and modern humans are. Why is there only one species on the planet right now within our genus?”
In the Classroom
While teaching, Lacy relates to her students on a personal level, sharing interesting anecdotes during lectures, and spending time with them outside the classroom.
“In my upper level anthropology course we are studying the human microbiome. I make my own Kombucha [tea fermented using with a symbiotic colony of bacteria and yeast] and they wanted to try it, so I brought some in for them since it relates to what they’re studying,” said Lacy, who has found CSUDH students to be very engaging. “We also had some Tepache, a fermented pineapple drink from Mexico simmering in the corner. I want students to know that I’m not just trying to relay information to them; that I’m an active knowledge creator.”
Like she did in St. Louis, Lacy plans to integrate her students into her research, and would like to purchase an X-ray machine for the anthropology department.
“I want to get students to come work in the lab on hundreds of fossil X-rays files that I’ve collected to look for specific pathologies,” said Lacy, who is the faculty adviser for the student Anthropology Club at CSUDH. “There are also other pathologies that can be collected from those X-rays that I’m not working on yet. I would love to train students to be able to recognize and score those pathologies. Then we could jointly publish the work without having to leave the country to do research.”
Studying the fossils of ancient humans can also provide significant insights for other fields, such as biology, health sciences, and human geography, according to Lacy. Pre-med students could also benefit from examining her research, as well as students majoring in occupational therapy, where practitioners–particularly in Southern California–work directly with individuals with diverse lineages.
“How can we contextualize what we are seeing in patterns in oral health today if we don’t understand the baseline level of oral health in earlier humans?” said Lacy. “The Paleo Diet is a good example of where such research could be useful. Many people say, ‘Ancient people were much healthier, so we should act and eat like they did.’ But I say no, periodontal disease was rampant back then. Close to 80 percent of all Neandertals had mild periodontal disease. So do we really want to be mimicking their diet?”