Today I Learned

[raklian]

While I already knew how it works, it was fascinating to watch it happen, especially at the end of the 2nd video below where it shows lightning being discharged through the wingtip.

[raklian]

[TrueAnimationFan]

Crabs can fly underwater.

This had me crying with laughter. It looks like an RC helicopter when it moves its claws that fast

[wjfox]

TIL: There is an organisation called the International Space Elevator Consortium (ISEC).

[Powers]

https://theconversation.com/blood-in-yo ... ver%20blue.

Sometimes blood can look blue through our skin. Maybe you’ve heard that blood is blue in our veins because when headed back to the lungs, it lacks oxygen. But this is wrong; human blood is never blue. The bluish color of veins is only an optical illusion. Blue light does not penetrate as far into tissue as red light. If the blood vessel is sufficiently deep, your eyes see more blue than red reflected light due to the blood’s partial absorption of red wavelengths.

https://www.wtamu.edu/~cbaird/sq/mobile ... eins-blue/

[wjfox]

wjfox: I live in the UK and worry that the birds in my garden get too cold in winter. It's around -2°C in London today. How do they stay warm? Are their feathers good at holding heat? Do they cope better than humans with cold?

ChatGPT: Birds have several adaptations that help them stay warm in cold temperatures, like those you're experiencing in London. Here are the key ways birds cope with the cold:

• Feather Insulation: Birds' feathers are excellent insulators. The outer feathers are waterproof and windproof, while the downy underlayer traps air, providing a layer of warm insulation. Birds can fluff up their feathers to trap even more air and increase insulation.
• Behavioral Strategies: Birds often adopt specific behaviors to conserve heat. They might seek shelter in dense foliage, under eaves, or in birdhouses to avoid the wind and retain heat. Roosting in groups is another common behavior, as it reduces the amount of exposed surface area and shares warmth.
• Shivering: Just like humans, birds can shiver to generate heat. This muscle activity increases their metabolic rate and helps to maintain body temperature.
• Metabolic Rate: Many small birds have a high metabolic rate, which helps to generate body heat. However, this also means they need a constant supply of food to maintain their energy levels.
• Tucking In: Birds often tuck their bills and one leg into their feathers to reduce heat loss. This posture minimizes exposed body parts.
• Fat Reserves: Some birds build up fat reserves in the winter. This not only provides insulation but also serves as an energy source.

Birds are generally better adapted to cold temperatures than humans due to these natural mechanisms. Their feathers, in particular, are far more effective at insulation than most of the clothing materials used by humans. However, extreme cold can still be challenging for them, especially if it impacts their food supply. Helping birds during winter by providing food and water can be beneficial, especially when natural food sources are scarce due to snow or ice.

[wjfox]

TIL: Jupiter is the oldest planet in our Solar System and pre-dates the Earth by 50 million years.

[wjfox]

TIL: Sweden and Norway were once united and known as the United Kingdoms.

This lasted from 1814 until 1905.

https://en.wikipedia.org/wiki/Union_bet ... and_Norway

[Powers]

TIL: Sweden and Norway were once united and known as the United Kingdoms.

This lasted from 1814 until 1905.

https://en.wikipedia.org/wiki/Union_bet ... and_Norway

https://en.wikipedia.org/wiki/Denmark%E2%80%93Norway

[Powers]