My hypothesis:
Humans invented hats because we were envious of the marvelous headgear in the animal world.
Let's talk about antlers, horns, ossicones & pronghorns.
#Antlers are shed & regrown every year, composed of bone that begins at a pedicle, base structure that remains after shedding. Antlers are extensions of the the skull.
Mechanism of growth similar to bone HEALING: cartilaginous tissue gives rise to bone coated in skin "velvet".
Antlers usually only form on males, with one exception: female reindeer grow shortened antlers, which may be functional for snow clearing, or challenge between females over scarce food resources.
The control of antler growth is evolutionary controlled, with phylogenetic parallels across species. In other words, the same genes work to control similar structures between say, a fallow deer and a moose.
At the end of a season, a type of cell that maintains bone, an 'osteoclast', degrades the connection between antler and skull.
Blood supply has long since been severed, so the loss is generally bloodless.
Antlers require a lot of nutrient, so tell us about health of the animal.
#Horn by contrast, is a bony extension of the skull that is covered in keratin, the same material in our fingernails.
They aren't typically shed: broken horns can be a serious injury because they're supplied by blood from a coronet structure at the base.
Horns are typically found in both male & females. Although we might think of them as "shorter" than antlers, that's not universally true.
Honorable mention is giraffid headgear: "ossicones", which are also bony extensions of the skull, but remain covered in skin throughout the animal's life.
These magnificent structures form in late gestation (so they're born with them) but don't fuse to skull until puberty.
The giraffe's cousin, the okapi, also have these ossicones, although a bit less iconic. It's not clear (to me) what function they serve.
Lastly, the oddball: pronghorns.
Found in the only surviving member of Antilocapridae, a group of New World antelope-like animals (that are not antelopes!).
They're shed annually like antlers, but covered in keratin like horns.
The Pronghorn is more closely related to modern giraffes than to African/Eurasian antelope & represents at least 11 million years of evolution from a common ancestor.
There were once 11 other antilocaprid ("antelope goats") species in North America, but only Pronghorn remains.
Let's be honest. If we could grow a giant rack of antlers, we'd all be inundated by "antler enhancement pills".
If we could grow horns, they'd offer horn extensions to women, have an elaborate industry of horn accessories.
On the whole, I think we're better off with the hats.
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This 1852 painting by William Firth depicts the moment in 1717 when English poet Alexander Pope declares his undying love to Lady Mary Wortley Montagu, and her response is a fit of laughter (brutal!).
Both characters are worth knowing in a little more depth.
Alexander Pope is best remembered for 18th century essays & poetry: "Rape of the Lock", Illiad & Odyssey translations. He coined phrases: "damn with faint praise" and "to err is human".
Spinal form of tuberculosis made him a hunchback, at full height he stood 4 ft 6 in (1.4 m).
He made enemies easily, made them the subject of satirical portrayals, as with the case of Lady Mary.
He spent most of his life striking back at her in prose for refusing his love, portraying her as vapid or immoral or of poor poetic talent.
Let's talk about Point Roberts, WA: the tiny American peninsula on Vancouver Island that can only be reached by driving 25 miles through Canada and clearing two international border crossings. It's < 5 sq miles, home to ~1,000 residents.
It's a very AMERICAN story.
Originally Coastal Squamish (Sḵwx̱wú7mesh Úxwumixw) lands, post-1812, the British & Americans co-occupied a land they called "Oregon Country" (US) or "Columbia District" (UK).
US Pres. James Polk was elected on a campaign of "Fifty-Four Forty or Fight".
What does that mean?
The belligerently proposed 54° 40'N Oregon boundary would have given much of the ice-free Pacific Coast to the US, landlocking Western Canada.
The US were prepared to fight the British over this. The British were not so keen on a prolonged war, so were willing to negotiate.
J.B.S Haldane: "The Universe is not only queerer than we suppose, but queerer than we CAN suppose."
Let's talk about the pea aphid, Acyrthosiphon pisum:
It can 'feed' on sunlight; gives birth to live, pregnant clone-babies & needs to be bacterially infected to survive.
1. Let's start with the weirdest fact first: these little bugs seem to be capable of feeding directly on sunlight, like the plants on which they feed.
They're nearly unique in the animal world in the ability to make a carotenoid photopigment.
Torulene is responsible for red-like color of some aphids.
Green or red/pink aphids produce more ATP in sunlight than they do in darkness; white aphids deficient in torulene do not, suggesting carotenoid is directly absorbing photons, transferring electrons to mitochondria.
What do cabbage, kale, broccoli, brussel sprouts, cauliflower, collard greens & kohlrabi have in common?
If you said "they're the same species of plant, selected for different qualities", you're correct!
Let's talk about the chameleon of the vegetable world, the #Brassica!
They're all Brassica oleracea, derived from the wild cabbage, which is itself part of the wild mustard FAMILY.
Brussel sprouts are cultivars selected for unopened lateral lead buds, broccoli & cauliflower for the unopened flowers, kale for leaves, kohlrabi for enlarged stem.
That's the basics, but there's an even larger family of Brassica whose genetic intercompatibility have produced endless combinations of cultivated crops!
Let's talk about the "triangle of U", named for 1935 paper by 'U Nagaharu' where he presented a theory of Brassica genetics.