5-6 metre beasts. Exotically patterned fur with thermal patches. Cute little horns. Really long tongues with lots of melanin (protects from sunburn). These beauties are a wonder to behold. And yes, I just described them as beauties and beasts.
Here are the 3 facts I love most about giraffes and why you should love them, too:
- Blood supply to neck and head
So the paper by Goetz and Keen (1957) was a little bit too technical for my liking, but essentially the giraffe’s neck height presents challenges for blood circulation. The giraffe’s heart has to be able to pump blood 1.8 metres upwards against gravity. To add to that, you know when you get up too quickly, you feel dizzy because the blood rushes away from your head thanks again to gravity? Imagine when a giraffe stoops its neck down below the level of its heart to drink. That’s blood rushing to the head. Then when it raises its neck, blood rushes away from the head. The reason they don’t bleed or faint is that there are these muscles all along the neck wall that help regulate the blood pressure so it is not too high or too low, and that’s as technical as I’d like to put it.
- Blood supply to legs
Giraffe legs are also around 1.8 metres in height, so blood probably needs help getting back up to the heart. Ever wondered why giraffe legs are a little bit on the skinny side? It’s because the skin is very tight around the legs to prevent the blood from pooling there (Sathar et al, 2010). It’s like wearing tights or stockings on a plane trip to prevent your feet and legs from being swollen by the time the plane lands.
Giraffes only need 2 hours of sleep per day (Whipple, 2014). Apparently it has to do with the environment and survival. Still, I wish I could sleep 2 hours and have enough energy for the rest of the day. As it is, I sleep 10 hours and still need a nanny nap. Especially on Sundays.
I think we can safely conclude that giraffes are pretty darn cool. Have I convinced you?
Special thanks to AT for suggesting this random topic!
Goetz, R & Keen, E 1957, ‘SOME ASPECTS OF THE CARDIOVASCULAR SYSTEM IN THE GIRAFFE’, Angiology, vol. 8, no. 6, p. 542.
Sathar, F, Ludo Badlangana, N, & Manger, PR 2010, ‘Variations in the thickness and composition of the skin of the giraffe’, Anatomical Record (Hoboken, N.J.: 2007), vol. 293, no. 9, pp. 1615-1627.
Whipple, T, 2014,’Giraffes need only two hours’ sleep while cuttlefish and octopus dream’, The Times, London (UK).