While watching a pair of ravens in flight the other day – they do put on a good display of synchronised flying – I suddenly wondered what it must have been like for the very first bird which took to the air. Who was this Orville or Wilbur of the avian world? Did it dream big and practice dashing along the ground, flapping, until it generated enough lift? Or did it slip from a cliff edge and find that, instead of plummeting to its death, the air below its wings caused it to glide gently earthward? Did its companions look and learn, daring one another to experiment with increasingly complex manoeuvres? How long did it take for flight to become a thing, who undertook the first migration, who was the first aerial predator, oh my, I have too many questions…
While we don’t have answers to many of these, we do now know which bird has taken flying to its most extreme. In the 1970’s, ornithologist Ronald Lockley hypothesised that swifts might never land during their sojourn in the southern summer (interestingly, the species name “Apus” means “footless” in Greek). Thanks to modern technology, specifically tiny, lightweight data logger/geolocators attached to the little birds, researchers have shown that swifts indeed spend a great deal of the time in the air – for some Common Swift this can be a whopping 10 months. The advantages to spending much of your life on the wing are that you are less likely to get caught (swifts have a high survival rate compared to many other birds and can live to 20 years old) and you probably won’t be worrying about parasite infestations. As for sleep, well, no-one’s really sure yet. Twice a day the swifts made an ascent to around 2500m and it is not yet known if this aids navigation or perhaps allows the birds to nap as they glide back down.
As always, there’s a lot more to discover.
Photo credit: Sally Adam
Photo caption: A grounded White-rumped Swift, rescued and released
