Professor Kyle Harper

The other that's been, I mean, I would say revolutionary is gene sequencing. And in particular, the kind of what are called high throughput gene sequencing technologies that make it

fast and relatively affordable to sequence huge amounts of DNA, DNA from people's bones that can tell us about their ancestry, but also at times about the identity of the pathogens that infected them and made them sick. So the rise of these new genetic technologies, which really are new, it's 15 years ago now that the first complete ancient human genome was published. So this is new.

fast and relatively affordable to sequence huge amounts of DNA, DNA from people's bones that can tell us about their ancestry, but also at times about the identity of the pathogens that infected them and made them sick. So the rise of these new genetic technologies, which really are new, it's 15 years ago now that the first complete ancient human genome was published. So this is new.

fast and relatively affordable to sequence huge amounts of DNA, DNA from people's bones that can tell us about their ancestry, but also at times about the identity of the pathogens that infected them and made them sick. So the rise of these new genetic technologies, which really are new, it's 15 years ago now that the first complete ancient human genome was published. So this is new.

For historians, this is really exciting. It's telling us about human population history, it's telling us about animal history, and it's telling us about microbe history.

For historians, this is really exciting. It's telling us about human population history, it's telling us about animal history, and it's telling us about microbe history.

For historians, this is really exciting. It's telling us about human population history, it's telling us about animal history, and it's telling us about microbe history.

Yeah, absolutely. A lot of diseases are caused by infectious agents. They're infectious diseases because something invades your body and causes the infection. And those are little organisms. They're usually bacteria or viruses. And those little organisms have genetic codes, so RNA or DNA. And under the right circumstances, it takes a little bit of luck. Bacteria are easier to find than viruses.

Yeah, absolutely. A lot of diseases are caused by infectious agents. They're infectious diseases because something invades your body and causes the infection. And those are little organisms. They're usually bacteria or viruses. And those little organisms have genetic codes, so RNA or DNA. And under the right circumstances, it takes a little bit of luck. Bacteria are easier to find than viruses.

Yeah, absolutely. A lot of diseases are caused by infectious agents. They're infectious diseases because something invades your body and causes the infection. And those are little organisms. They're usually bacteria or viruses. And those little organisms have genetic codes, so RNA or DNA. And under the right circumstances, it takes a little bit of luck. Bacteria are easier to find than viruses.

There are DNA viruses and RNA viruses. RNA viruses are like measles. It's very hard to recover. But with the right pathogen and the right circumstances of preservation, it's sometimes possible to get the DNA of the microbe that killed a specific individual at a specific point in time. And that has really, really revolutionized what we know about the past of human health, of pandemics.

There are DNA viruses and RNA viruses. RNA viruses are like measles. It's very hard to recover. But with the right pathogen and the right circumstances of preservation, it's sometimes possible to get the DNA of the microbe that killed a specific individual at a specific point in time. And that has really, really revolutionized what we know about the past of human health, of pandemics.

There are DNA viruses and RNA viruses. RNA viruses are like measles. It's very hard to recover. But with the right pathogen and the right circumstances of preservation, it's sometimes possible to get the DNA of the microbe that killed a specific individual at a specific point in time. And that has really, really revolutionized what we know about the past of human health, of pandemics.

Exactly. I think it's very easy for us to forget how radically population-level human health has been transformed over the last century and a half. This transition has revolutionized everything about our world. It's prolonged life expectancies by two to three times. In the Roman world,

Exactly. I think it's very easy for us to forget how radically population-level human health has been transformed over the last century and a half. This transition has revolutionized everything about our world. It's prolonged life expectancies by two to three times. In the Roman world,

Exactly. I think it's very easy for us to forget how radically population-level human health has been transformed over the last century and a half. This transition has revolutionized everything about our world. It's prolonged life expectancies by two to three times. In the Roman world,

We don't know, and there's probably not like one stable number, but if I want to pin down a number, life expectancy at birth is probably something like 25 years, plus or minus a few years. A lot of that's infant mortality, a lot of it's childhood mortality, but all the same, the average life expectancy is so much worse in the pre-modern period than the modern period.

We don't know, and there's probably not like one stable number, but if I want to pin down a number, life expectancy at birth is probably something like 25 years, plus or minus a few years. A lot of that's infant mortality, a lot of it's childhood mortality, but all the same, the average life expectancy is so much worse in the pre-modern period than the modern period.

We don't know, and there's probably not like one stable number, but if I want to pin down a number, life expectancy at birth is probably something like 25 years, plus or minus a few years. A lot of that's infant mortality, a lot of it's childhood mortality, but all the same, the average life expectancy is so much worse in the pre-modern period than the modern period.

There's several variables that account for that. The most fundamental one is that they don't have modern science. So we are lucky to benefit from modern science, which helps us understand the body, helps us understand the infectious cause of infectious diseases, helps us develop things like vaccines, hygiene, water treatment, antibiotics, other pharmaceuticals. None of those are available.