Jacob Tennessen
@jacobphd.bsky.social
Scientist errant. Genetics, evolution, whimsy, awe. https://scholar.harvard.edu/jtennessen
🧬🦟🐌🩸👤🦠🍓🐸🧬
🧬🦟🐌🩸👤🦠🍓🐸🧬
You can't win, for I've already drawn you as the disheveled Putative First Animal and myself as the sleek and sophisticated Complex Early Animal.
November 11, 2025 at 5:28 PM
You can't win, for I've already drawn you as the disheveled Putative First Animal and myself as the sleek and sophisticated Complex Early Animal.
This says Anopheles mosquitoes crossed the Atlantic when it was ~2/3 of its modern width, instead of the conventionally stated Mesozoic timing when the distance was short. Is it plausible? Mosquitoes are delicate and absent from many remote islands, but life finds a way…
www.pnas.org/doi/10.1073/...
www.pnas.org/doi/10.1073/...
November 6, 2025 at 11:46 PM
This says Anopheles mosquitoes crossed the Atlantic when it was ~2/3 of its modern width, instead of the conventionally stated Mesozoic timing when the distance was short. Is it plausible? Mosquitoes are delicate and absent from many remote islands, but life finds a way…
www.pnas.org/doi/10.1073/...
www.pnas.org/doi/10.1073/...
Only one predator species chooses its prey based on what it senses the prey has eaten. Specifically, it wants prey full of human (or other vertebrate) blood! Meet Evarcha culicivora, the spider that prefers blood-fed mosquitoes. Called the vampire spider, but this is misleading: it EATS vampires.
November 6, 2025 at 5:05 AM
Only one predator species chooses its prey based on what it senses the prey has eaten. Specifically, it wants prey full of human (or other vertebrate) blood! Meet Evarcha culicivora, the spider that prefers blood-fed mosquitoes. Called the vampire spider, but this is misleading: it EATS vampires.
Toxoplasma isn't "intelligent" but it manipulates the behavior of rodents & maybe other mammals. A brainless algorithm formed by natural selection to hijack brains.
AI need not know what it's doing either, but versions that engage with human psyche so as to favor their own propagation will prosper.
AI need not know what it's doing either, but versions that engage with human psyche so as to favor their own propagation will prosper.
November 3, 2025 at 3:16 PM
Toxoplasma isn't "intelligent" but it manipulates the behavior of rodents & maybe other mammals. A brainless algorithm formed by natural selection to hijack brains.
AI need not know what it's doing either, but versions that engage with human psyche so as to favor their own propagation will prosper.
AI need not know what it's doing either, but versions that engage with human psyche so as to favor their own propagation will prosper.
An amusing subreddit to browse is /r/Birdsfacingforward
October 31, 2025 at 6:19 AM
An amusing subreddit to browse is /r/Birdsfacingforward
Wasting away again in Amanitaville
October 29, 2025 at 8:13 PM
Wasting away again in Amanitaville
A "monster" was originally a biological abnormality like a birth defect, believed to be an omen. But it's ableist and scientifically inaccurate to classify births as normal vs abnormal: every baby has unique mutations as well as non-genetic quirks. You are a monster, so do the mash!
October 29, 2025 at 3:28 PM
A "monster" was originally a biological abnormality like a birth defect, believed to be an omen. But it's ableist and scientifically inaccurate to classify births as normal vs abnormal: every baby has unique mutations as well as non-genetic quirks. You are a monster, so do the mash!
The move to ban Red 40 dye is comical since it's almost literally a red herring. The problems it's supposed to solve are real, and we don't need it, but ditching it won't make America any healthier. An influencer will call it a poison but a scientist will tell you that the dose makes the poison.
October 29, 2025 at 2:15 AM
The move to ban Red 40 dye is comical since it's almost literally a red herring. The problems it's supposed to solve are real, and we don't need it, but ditching it won't make America any healthier. An influencer will call it a poison but a scientist will tell you that the dose makes the poison.
Fuegian “dogs" were not dogs but a partially domesticated form of the fox-like Patagonian culpeo, bred by the Selk’nam people for aid in hunting. A genocide c. 1900 targeted these pets and drove them extinct, though the Selk’nam survived.
Human ingenuity, and human cruelty, shape genetic diversity.
Human ingenuity, and human cruelty, shape genetic diversity.
October 26, 2025 at 6:38 PM
Fuegian “dogs" were not dogs but a partially domesticated form of the fox-like Patagonian culpeo, bred by the Selk’nam people for aid in hunting. A genocide c. 1900 targeted these pets and drove them extinct, though the Selk’nam survived.
Human ingenuity, and human cruelty, shape genetic diversity.
Human ingenuity, and human cruelty, shape genetic diversity.
For a great satire of American gun culture, see the first chapter of From the Earth to the Moon written in 1865. I guess we've always been like this.
October 22, 2025 at 1:02 AM
For a great satire of American gun culture, see the first chapter of From the Earth to the Moon written in 1865. I guess we've always been like this.
Happy Indigenous Peoples’ Day! This photo from Alaska 1914 is sad, but also has potential as a modern meme.
October 13, 2025 at 5:52 PM
Happy Indigenous Peoples’ Day! This photo from Alaska 1914 is sad, but also has potential as a modern meme.
Mushroom friends, Washington Cascades
October 10, 2025 at 7:50 PM
Mushroom friends, Washington Cascades
"Otter" and "Hydra" are really the same word, modern versions of the Proto-Indo-European *udros for "water creature." You can still hear it in the names.
October 4, 2025 at 4:57 AM
"Otter" and "Hydra" are really the same word, modern versions of the Proto-Indo-European *udros for "water creature." You can still hear it in the names.
What in the Hatch Act is happening to federal websites?
October 2, 2025 at 1:44 PM
What in the Hatch Act is happening to federal websites?
This makes me so happy. Scicomm matters.
October 1, 2025 at 1:48 AM
This makes me so happy. Scicomm matters.
Acetaminophen was first used on humans in 1887 yet Jules Verne described Phileas Fogg in 1872 presumably by observing the personalities of real humans who existed at that time.
September 24, 2025 at 1:45 AM
Acetaminophen was first used on humans in 1887 yet Jules Verne described Phileas Fogg in 1872 presumably by observing the personalities of real humans who existed at that time.
How it started: insecticide resistance emerges in African Anopheles in early 2000s
How it's going: basically everywhere.
In less than a human generation, our main protective tool against malaria is reduced to a fraction of its former power. Many mosquitoes now resist 10x the formerly lethal dose.
How it's going: basically everywhere.
In less than a human generation, our main protective tool against malaria is reduced to a fraction of its former power. Many mosquitoes now resist 10x the formerly lethal dose.
September 19, 2025 at 3:30 PM
How it started: insecticide resistance emerges in African Anopheles in early 2000s
How it's going: basically everywhere.
In less than a human generation, our main protective tool against malaria is reduced to a fraction of its former power. Many mosquitoes now resist 10x the formerly lethal dose.
How it's going: basically everywhere.
In less than a human generation, our main protective tool against malaria is reduced to a fraction of its former power. Many mosquitoes now resist 10x the formerly lethal dose.
Stuff I've written about biology that I think is cool (and you might too):
General musings:
adaptivediversity.wordpress.com
The Emoji Guide to Human Genetic Diversity:
scholar.harvard.edu/jtennessen/e...
More emoji-based science communication:
scholar.harvard.edu/jtennessen/b...
General musings:
adaptivediversity.wordpress.com
The Emoji Guide to Human Genetic Diversity:
scholar.harvard.edu/jtennessen/e...
More emoji-based science communication:
scholar.harvard.edu/jtennessen/b...
September 17, 2025 at 4:16 PM
Stuff I've written about biology that I think is cool (and you might too):
General musings:
adaptivediversity.wordpress.com
The Emoji Guide to Human Genetic Diversity:
scholar.harvard.edu/jtennessen/e...
More emoji-based science communication:
scholar.harvard.edu/jtennessen/b...
General musings:
adaptivediversity.wordpress.com
The Emoji Guide to Human Genetic Diversity:
scholar.harvard.edu/jtennessen/e...
More emoji-based science communication:
scholar.harvard.edu/jtennessen/b...
Lewis Thomas's The Medusa and the Snail tells of a fascinating symbiosis. A tiny jellyfish lives on sea slugs. It produces free-floating predatory offspring. When a slug gets ingested it doesn't die. It eats most of the jellyfish leaving a tiny living disk, as at the start.
The story isn't true.
The story isn't true.
September 17, 2025 at 1:44 AM
Lewis Thomas's The Medusa and the Snail tells of a fascinating symbiosis. A tiny jellyfish lives on sea slugs. It produces free-floating predatory offspring. When a slug gets ingested it doesn't die. It eats most of the jellyfish leaving a tiny living disk, as at the start.
The story isn't true.
The story isn't true.
In these polarized times, it’s nice to find near-universal agreement on something.
September 8, 2025 at 11:02 PM
In these polarized times, it’s nice to find near-universal agreement on something.
Cow jokes aside, this actually comes from a fantastic project to physically trap mosquitoes lured by sleeping humans and thus kill the insects without insecticides, preventing the evolution of insecticide resistance. A superb practical application of Darwinian thinking.
August 31, 2025 at 11:41 PM
Cow jokes aside, this actually comes from a fantastic project to physically trap mosquitoes lured by sleeping humans and thus kill the insects without insecticides, preventing the evolution of insecticide resistance. A superb practical application of Darwinian thinking.
Laypeople: The Spherical Cow (en.wikipedia.org/wiki/Spheric...) is just a joke and scientists don't really do that, right?
Actual peer reviewed papers:
Actual peer reviewed papers:
August 31, 2025 at 5:12 AM
Laypeople: The Spherical Cow (en.wikipedia.org/wiki/Spheric...) is just a joke and scientists don't really do that, right?
Actual peer reviewed papers:
Actual peer reviewed papers:
But seriously, “mitochondrial challenge” is not a medically meaningful term, and you certainly can’t diagnose it by looking at someone.
Source: You should know this from like 6th grade science class.
Source: You should know this from like 6th grade science class.
August 28, 2025 at 3:25 PM
But seriously, “mitochondrial challenge” is not a medically meaningful term, and you certainly can’t diagnose it by looking at someone.
Source: You should know this from like 6th grade science class.
Source: You should know this from like 6th grade science class.