Hummingbirds and Swifts

     As a result of my recent review of Sara Gibson's excellent book, Swifts and Us, and some subsequent correspondence I had with the author, I was asked by Hilary Melton-Butcher, that peripatetic seeker of knowledge, to explain the taxonomic affinity between hummingbirds and swifts. Like Hilary, perhaps many of you will find this fact of common ancestry a little surprising, but it is nonetheless, an established truth - subject to some some discussion about whether certain anatomical features reflect ancestry or convergent evolution! We may set that conjecture aside here.

     I don't think I can explain this without getting at least a little technical, so forgive me if I am causing your eyes to roll back in your head. It would easily be possible to make this post extremely lengthy, but I am going to try to cut to the essentials, while giving Hilary (and the rest of you) the explanation she is looking for.

     Both hummingbirds and swifts, along with treeswifts, are placed in the order Apodiformes, which means "without feet" and reflects the most significant similarity between the two. Feet have not been eliminated, of course, but they are barely functional in either species. Swifts, in fact, spend virtually all their lives on the wing, eating, sleeping and even mating in the air, using their feet which have sharp claws only to cling to the vertical surfaces on which they construct their nests. Hummingbird feet enable them to grip a branch but beyond that they are pretty much useless.

Cuban Emerald (Riccordia ricordii), Cienága de Zapata, Cuba

      The order Apodiformes contains the following families:

Treeswifts - Hemiprocnidae

Swifts - Apodidae

Hummingbirds - Trochilidae

     Shared characters are:

- modified cervical musculature

- the skeleton of flight apparatus

- wing muscle innervation, or feather tracts

- small to tiny birds with 10 primary feathers

- 6 - 11 significantly shorter secondaries

- all species are nidicolous (altricial)

- all species are gymnopaedic (naked, helpless young) 

     That, in a nutshell gives you the reasons for their grouping in one order.

Anna's Hummingbird (Calypte anna), Somenos Marsh, Duncan, BC, Canada

      There are 359 species of hummingbird in the world and I have seen 137 of them.

Sword-billed Hummingbird (Ensifera ensifera), Cabañas San Isidro, Ecuador

Crowned Woodnymph (Thalurania colombica), Cerro Azul, Panama

     Treeswifts are a small family comprising only four members and I have seen two species in Cambodia. We have no pictures of our own to share so this image is taken from the internet.

Crested Treeswift (Hemiprocne comata)

     Of the 113 species of swift in the world I have seen thirty, yet have never been able to get a photograph, nor has Miriam, and of the two of us, she would be more likely than I am to succeed.

     So, once again, I resort to the internet.

Chimney Swift (Chaetura pelagica)

     In addition, Franc Gorenc kindly sent me a couple of his pictures.

Antillean Palm Swift (Tachornis phoenicobia), Varadero, Cuba

Alpine Swift (Tachymarptis melba) chasing insect, Pag Island, Croatia

     I hope this gives you the information you are seeking, Hilary, and with luck it will enlighten others too.