Like I mentioned in the title, one of the most incredible facts I know is that each red blood cell contains about 270 million hemoglobin molecules, and there are roughly 20 to 30 trillion red blood cells in the human body.
Less time has passed between T. rex and H. sapiens than between T. rex and Stegosaurus.
Naked Mole Rats are rodents that behave like termites. The queen removes the males’ ability to reproduce and influences females to produce hormone-rich urine. They might be the only mammals besides humans to create communal latrines for their waste, they rely on external temperatures, and they are almost completely resistant to cancer.
The naked mole rat can also survive for hours in low oxygen environments, including up to 16 minutes without oxygen. They have special adaptations for living in large underground nests where oxygen levels drop and carbon dioxide increases.
Oral contraceptives are really interesting.
I quite like this method.
Bats have nipples near their armpits, and they can fly while feeding their babies.
This makes me oddly happy.
That’s just nature being really convenient.
Wow. Joel Schumacher really messed that up.
Aphids are born already pregnant.
Only a few species of mites reproduce by ‘telescoping generational parthenogenesis’.
Aphids are not mites. They are insects, and yes, most common aphid species are “born pregnant.”
The first cells that form in an embryo are heart cells. The second are liver cells.
That makes a lot of sense. First a heart to distribute nutrients and then the most important organ.
These are rough estimates that can vary, but on average, cell counts show we have a 1:1 ratio of human cells to bacterial cells (50% human). If we exclude red blood cells that don’t have nuclei and don’t divide, the ratio is 1:10 (10% human). The situation gets even stranger when we consider our genetics. Sampling mRNA from all over the body shows that on average, we have a 1:100 ratio of human genes to non-human genes. In a healthy adult, most of the diverse proteins doing work in our bodies are not human.
This really changes how we think about what it means to be human.
When I share this with my students and they don’t believe these bacteria are part of us, I ask them to think about cows that would starve without cellulose-fermenting bacteria. If a cow can’t survive without these bacteria, it makes sense to consider the bacteria part of cows.
It’s an interesting perspective, but human cells are much larger than bacterial cells, so the percentage of our body made up of human cells is still much higher than bacteria.
Agreed. Biomass is not the same as cell count.
Are any bacterial proteins transported into our cells, or do the tasks you mentioned only happen in the gut?
Recent research on gut microbiota makes this even more fascinating.
If gut bacteria influence what your body craves, it brings up some interesting questions about free will.
Don’t you think it’s more like the bacteria are just signaling what they need to keep things running, like any other small part of you? Since it’s happening inside your body to keep it in good shape, the bacteria’s behavior isn’t much different from a muscle cell needing magnesium, even if the methods are different.
It’s not like the bacteria are sending commands to your brain to trick you into doing things against your will, right? Right?!
I don’t know all the details about what’s happening in the gut, but I’m curious.