Dr. Chloe Josefson
@chloejosefson.bsky.social
Assistant Prof/New PI at North Carolina Central. Organismal physiology of lactation 🐭🐁🍼. Female-centered biology. Mom. STEMinist👩🔬. She/her. Views my own.
Narwhal follows another Arctic char, flushing it to the surface only to be snatched by a glaucous gull (Larus hyperboreus) (O'Corry-Crowe et al. 2025). #2025MMM
March 27, 2025 at 1:15 AM
Narwhal follows another Arctic char, flushing it to the surface only to be snatched by a glaucous gull (Larus hyperboreus) (O'Corry-Crowe et al. 2025). #2025MMM
Cold-water drowning can happen in minutes in the Arctic Sea: "Thermal conductivity of water is 20 to 25 times that of air, so a body will lose heat approximately three times faster in water than in air." (Rolf & Gallagher 2018) #2025MMM
a dalmatian dog is sitting in the snow with a quote from the movie 101 dalmatians .
ALT: a dalmatian dog is sitting in the snow with a quote from the movie 101 dalmatians .
media.tenor.com
March 27, 2025 at 1:14 AM
Cold-water drowning can happen in minutes in the Arctic Sea: "Thermal conductivity of water is 20 to 25 times that of air, so a body will lose heat approximately three times faster in water than in air." (Rolf & Gallagher 2018) #2025MMM
Narwhal's large, hollow horn is aimed at Zebra, who is treading water with greater and greater difficulty... until... Zebra sinks below the icy water's surface... forever #2025MMM
March 27, 2025 at 1:13 AM
Narwhal's large, hollow horn is aimed at Zebra, who is treading water with greater and greater difficulty... until... Zebra sinks below the icy water's surface... forever #2025MMM
...Zebra grows sluggish as the blood vessels in his legs constrict to redirect blood towards core organs. Zebra's legs become tired as his muscles run out of available energy after shivering in hopes of producing body heat (thermogenesis) #2025MMM
March 27, 2025 at 1:13 AM
...Zebra grows sluggish as the blood vessels in his legs constrict to redirect blood towards core organs. Zebra's legs become tired as his muscles run out of available energy after shivering in hopes of producing body heat (thermogenesis) #2025MMM
Though many mammals exhibit some degree of the mammalian diving reflex (or response), it is much stronger in aquatic mammals like Narwhal than terrestrial species. This physiological reflex is triggered by submersion in cold water & likely helps preserve oxygen stores (Godek & Freeman 2022) #2025MMM
March 27, 2025 at 1:11 AM
Though many mammals exhibit some degree of the mammalian diving reflex (or response), it is much stronger in aquatic mammals like Narwhal than terrestrial species. This physiological reflex is triggered by submersion in cold water & likely helps preserve oxygen stores (Godek & Freeman 2022) #2025MMM
As Narwhal returns from the depths, he spots something strange moving at the surface above. Narwhal’s laterally-oriented, smaller optic nerve canals mean that he likely has reduced depth perception but a wider field of view (monocular vision) (Racicot et al. 2018) #2025MMM
March 27, 2025 at 1:10 AM
As Narwhal returns from the depths, he spots something strange moving at the surface above. Narwhal’s laterally-oriented, smaller optic nerve canals mean that he likely has reduced depth perception but a wider field of view (monocular vision) (Racicot et al. 2018) #2025MMM
Zebra’s legs “stride powerfully underwater” (Stone 2008) as he attempts to swim to land he assumes would be surely upstream… but where? #2025MMM
March 27, 2025 at 1:10 AM
Zebra’s legs “stride powerfully underwater” (Stone 2008) as he attempts to swim to land he assumes would be surely upstream… but where? #2025MMM
But the water is much colder than Zebra was expecting. MMMagic has transported this odd-toed ungulate to the open waters of Baffin Bay, where sea ice is reaching its maximum coverage this time of year (Harning et al. 2021). #2025MMM
March 27, 2025 at 1:09 AM
But the water is much colder than Zebra was expecting. MMMagic has transported this odd-toed ungulate to the open waters of Baffin Bay, where sea ice is reaching its maximum coverage this time of year (Harning et al. 2021). #2025MMM
In the grasslands of the Mountain Zebra National Park in S. Africa, Zebra has just finished grazing for grasses and is at a watering hole for his daily drink of water (Penzhorn 1988). He takes a few steps into the water. #2025MMM
March 27, 2025 at 1:08 AM
In the grasslands of the Mountain Zebra National Park in S. Africa, Zebra has just finished grazing for grasses and is at a watering hole for his daily drink of water (Penzhorn 1988). He takes a few steps into the water. #2025MMM
Narwhal's fishy playmate makes a quick escape by rapidly swimming in the opposite direction (O'Corry-Crowe et al. 2025). Narwhal plunges deeper into the Bay. #2025MMM
March 27, 2025 at 1:06 AM
Narwhal's fishy playmate makes a quick escape by rapidly swimming in the opposite direction (O'Corry-Crowe et al. 2025). Narwhal plunges deeper into the Bay. #2025MMM
The function of Narwhal’s tusk (actually, a long, spiraled tooth!) is unclear, but very recent work shows that they are used in prey capture and in “exploration and likely play” (O’Corry-Crowe et al. 2025). #2025MMM
March 27, 2025 at 1:06 AM
The function of Narwhal’s tusk (actually, a long, spiraled tooth!) is unclear, but very recent work shows that they are used in prey capture and in “exploration and likely play” (O’Corry-Crowe et al. 2025). #2025MMM
TONIGHT, we find Narwhal in the North Water Polynya in the northern Baffin Bay region of the Arctic. Narwhal swims near the surface, his tusk closely pursuing a single Arctic char (Salvelinus alpinus). #2025MMM
March 27, 2025 at 1:05 AM
TONIGHT, we find Narwhal in the North Water Polynya in the northern Baffin Bay region of the Arctic. Narwhal swims near the surface, his tusk closely pursuing a single Arctic char (Salvelinus alpinus). #2025MMM
Mountain Zebra are increasing though still listed as vulnerable by IUCN due to habitat loss/encroachment, hunting & trapping, and drought (Gosling et al. 2019). Zebra have long been threatened w/ the 1st hunting ban in 1742 and populations nearing extinction in early 1900’s (Penzhorn 1988). #2025MMM
March 27, 2025 at 1:03 AM
Mountain Zebra are increasing though still listed as vulnerable by IUCN due to habitat loss/encroachment, hunting & trapping, and drought (Gosling et al. 2019). Zebra have long been threatened w/ the 1st hunting ban in 1742 and populations nearing extinction in early 1900’s (Penzhorn 1988). #2025MMM
Narwal’s adaptations leaves them w/ little physiological flexibility to adjust swimming & diving behavior in response to rising ocean temperatures and restricts them to specific ecological niches vulnerable to the effects of climate change (Williams et al. 2011). #2025MMM
March 27, 2025 at 1:02 AM
Narwal’s adaptations leaves them w/ little physiological flexibility to adjust swimming & diving behavior in response to rising ocean temperatures and restricts them to specific ecological niches vulnerable to the effects of climate change (Williams et al. 2011). #2025MMM
Narwal are physiologically adapted for icy waters w/ key diving muscles having high amounts of slow-twitch oxidative fibers that allow for endurance & myoglobin that allows for prolonged diving (Williams et al. 2011). #2025MMM
March 27, 2025 at 1:01 AM
Narwal are physiologically adapted for icy waters w/ key diving muscles having high amounts of slow-twitch oxidative fibers that allow for endurance & myoglobin that allows for prolonged diving (Williams et al. 2011). #2025MMM
Narwhal are physiologically adapted for icy waters with key diving muscles having high amounts of slow-twitch oxidative fibers that allow for endurance & myoglobin that allows for prolonged diving (Williams et al. 2011). #2025MMM
March 27, 2025 at 12:58 AM
Narwhal are physiologically adapted for icy waters with key diving muscles having high amounts of slow-twitch oxidative fibers that allow for endurance & myoglobin that allows for prolonged diving (Williams et al. 2011). #2025MMM
Buffalo looks up from a patch of tall grasses to survey the strange black-and-white creature. Cape Buffalo gives a warning snort and then... #2025MMM
March 25, 2025 at 1:07 AM
Buffalo looks up from a patch of tall grasses to survey the strange black-and-white creature. Cape Buffalo gives a warning snort and then... #2025MMM
Unsure of her surroundings, Tapir lets out a squeal followed by a "hiccup" indicating her fear and agitation (Gilmore 2007; Gearty 2012; Tawa 2021) #2025MMM
March 25, 2025 at 1:07 AM
Unsure of her surroundings, Tapir lets out a squeal followed by a "hiccup" indicating her fear and agitation (Gilmore 2007; Gearty 2012; Tawa 2021) #2025MMM