Bioarchaeology frequently incorporates chemistry; I work with several people who use chemical analysis of ancient human bones to reconstruct past societies. There's a couple common methodologies:

• Strontium Isotope Analysis Strontium isotope analysis takes advantage of the fact that different regions have different ratios of strontium isotopes in their soils. That strontium works its way up the food chain, eventually reaching humans and being incorporated into out growing bones. Your body can use Strontium-87 and Strontium-86 interchangeably, so the ratio in that region's soil is reflected in the strontium in your bones. Now, while most bones will grow and repair throughout your life, your teeth do not. Once your adult teeth are developed, that's it. They push out your baby teeth, the tooth fairy comes, and you're stuck with those teeth. This means that even in adults, your teeth will have a ratio of strontium isotopes that corresponds to where you grew up. This is incredibly useful for studying ancient migration patterns, among other things. Where did the settlers who built this colony come from? Was this group sacrificing local people or foreigners? Do foreigners live in certain parts of this city? The same type analysis can be done with oxygen isotopes, which vary across water sources.

• Stable Carbon Isotope Analysis Typical photosynthesis produces a 3-carbon molecule during its first stage. Some plants have evolved a more resilient form of photosynthesis that produces a similar product by proxy of an additional step. The ratios of Carbon-12 to Carbon-13 is different in each of these processes, and that ratio is maintained in anything that eats that plant. Certain key crops, like maize and millet, use the second photosynthesis pathway, called C4. Thus, we can study the carbon isotope ratios in bone samples to reconstruct ancient diets. In a region like the highland Andes, where maize has to be imported from lower elevations, determining who was eating it can be valuable information.

• Nitrogen Isotope Analysis Animals excrete more Nitrogen-14 as waste compared to Nitrogen-15. When the animal dies and gets eaten, the predator is consuming a higher ratio of ^15 N to ^14 N than the first animal did. That means that organisms at higher trophic levels have a significantly higher ^15 N percentage. If a person eats more meat, they'll have a higher ^15 N to ^14 N ratio.

There's plenty of other developing methodologies in need of testing. Sulphur isotopes have been proposed to differentiate freshwater and terrestrial meat sources, while stronitum-barium-calcium ratios may provide higher resolution geographic data compared to simpler strontium analysis.

I often use chemistry in my own work at the Field Museum's Elemental Analysis Facility. The bulk of my work uses X-Ray Fluorescence equipment, which zaps things with X-rays, records the fluorescence wavelengths they send back, and identifies elemental signatures. There's even handy portable "zappers" (the technical term of course) that we take in the field. I've also used Inductively Coupled Plasma Mass Spectrometry, which shoots things with a laser to vaporize the tiniest bit into a gas that can be run through a mass spectrometer. The range of elements that ICP-MS can detect is much greater: XRF can distinguish no more than 15 elements, ICP-MS can detect nearly 50.

Once we have the data on what trace elements are present in an object, we can compare those results with survey data on places the material for that object may have come from. Any geologic material will contain certain amounts of random metal impurities, so we try to match the signatures in an artifact to those in a quarry, mine, or clay bank. This can be used for most anything. Obsidian is a common target for XRF analysis because obsidian has so few sources to compare against. We zap temple walls to compare with sandstone quarries, we zap metal to see what mines they may have come from. I've zapped giant colonial Spanish jars used for distilling grapes to see if they're made from local Peruvian clay or were imported from Spain. Heck, I've a friend who wants to zap seashells.

This is just a sampling of "archaeometry" or "archaeological science." There's all kinds of room for pretty much any science you want in archaeology, as long as you can prove that it helps us understand past societies better. I didn't even touch on the strictly biological, non-chemistry stuff. There's standard osteology, both in bioarchaeology (human remains) or zooarchaeology (faunal remains). There's all kinds of botanical studies, from pollen and starch grains to textile analysis.

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For some reading on these methods

• This article by Tiffany Tung is the most approachable for isotope analysis of human remains. It addresses the practice of "trophy heads," dismembered heads that appear frequently in the art of Peru's Wari culture and of which there are a few actual examples, complete with drilled holes in their skull to run a string through for carrying or tying to a belt. The exact reason is unknown. Are these war trophies? Sacrificial victims? Family members carried in memorial? Tung uses strontium isotope analysis to compare these heads to individuals in local cemeteries, and finds out that many of the heads were taken from foreigners.

• In this article, Nicola Sharatt examines trade and ceramic production within in the Tiwanaku empire in Bolivia. Tiwanaku is known for its distinctive, unified art style- but were these things produced in a central location and distributed, or did local artists copy styles produced in core cities? ICP-MS analysis links Tiwanaku ceramics at Sharatt's field sites to local clay quarries, suggesting that very few vessels were imported.

• Here Christina Torres-Rouff, et al., invetigate what happened to a desert oasis site in Chile when it fell under the influence of the Tiwanaku. It had been hypothesized that the oasis was colonized by people from the Tiwanaku heartland, became a new elite class in the area. Using nitrogen and carbon isotopes, they show that diets of people in the study area diversified, suggesting class stratification, even though strontium analyses showed that this was not due to the arrival of new people.

I've stuck all these articles here, along with some other ones that explain their techniques well and present a lot of the processes.

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How do you get there? Grad school, mostly. Don't get a Phd in the social sciences.. You're probably a good person, don't waste your life. Admittedly, an archaeology/anthropology grad degree will be better than a history one. There is an active and necessary professional archaeology field outside of academia, and you can do something in it with an MA. But if you want to do straight-up research instead of government contract work, you'll need a PhD. Job prospects are slight, slightly better than for history. A PhD archaeology is feasible, but it requires an enormous initial investment. Most importantly, you'll want to look for a field school to attend before you graduate college. If that's some you're interested in, and want to keep your biology focus, I'd glad to help you find schools with an emphasis on that.

Any job with Paleo in the title is a good combination of history and science. For example, when I was in college I was drawn to Paleoecology. This is the study of not so much the bones of ancient animals as it is the study of the environment that they lived in. You would use process such as pollen analysis to determine what kind of plants were around, and from that determine the temperature and humidity of the area. Also Dendrochronology and trace fossils, heck even the depth of fossil footprints would all be combined to try to determine the environment. During my time in University, Dendrochronology had just been used to discover that carbon dating was inaccurate, due to higher or lower levels of carbon in the atmosphere. They used the study of tree growth rings to re-calibrate carbon dating.

Also if this is the wrong subreddit then feel free to direct me to a more suitable one