How do Birds Identify their own Species?

On television just over a month ago, there was a series that charted the migration of the human animal out of Africa where human evolved. Over the five hour long episodes the programme showed via the archaeology and genetics how human populations expanded across the globe. Even covering new research that shows that humans were in the Americas before the Clovis peoples.

It was a very entertaining series and well worth watching. However, it was a comment regarding the discovery and colonisation by Europeans, of the Americas, that stuck in my mind. That when the Europeans found the Americas they failed to recognise of fellow man as human. As part of my ethnic heritage is Scottish my skin colour is more blue than white, its cold up in Scotland, genetically I am only white as in the northern regions that are Europe we evolved to be paler skinned so we could absorb more sunlight to create vitamin D. We are ultimately all from black Africans.

This is where I can not understand racist thinking or logic. Even when I was a child I could not understand how in History people could fail to see other races as being our fellow humans. It must have been cultural conditioning that twisted the logic. I have often wondered what the world would be like if we had seen other races as our fellow man.

Before I go on, much of the science I already knew, I had discovered the most of this from the magazine Science, the journal of the Triples AS ( The American Association for the Advancement of Science). I have often thought that with my interests and social skills I could join the cast of “Big Bang Theory”

But being serious, it must have been cultural evolution that stopped fellow humans seeing shared humanity. However, this posting is not about racism, but about how other species recognise each other. While personally I can not understand how people can fail to see other humans, the fact that we did, does raise some interesting questions.

As humans can misidentify different birds that are similar, the question is do birds have difficulty identifying each other?

Well the answer is no. Birds of the same species can not only identify their own species, but individual birds. Across the world Birders call small brown birds LBJs (Little Brown Jobs) as at a distance several different species will look the same. It can be subtle differences in plumage, or the shape of the bill, or colour of the legs that enable us humans to tell the difference. Also we can use the songs and calls of the birds to tell the difference between species. As do the birds. The problem though for human birders is that unless you know the call or song even that can mean that we can fail to identify the bird unless you can see the bird and the song is a standard song. I personally have been confused by a Willow warbler that I saw in a different region of the UK. It was not until later that I discovered that some birds have a regional accent. So it is not only difficult understanding human accents but the birds too.

However, this regional accent appears to be a factor in species diversion, and was why some early reintroduction programmes failed. As simply the introduced birds were not mating with any residents. As simply the song sounded different.

Sound though is not the only way that birds recognise each other, as birds use sight as well. Birds have eyesight that is twenty times sharper than humans have. Just think of a hawk that can spot a mammal from altitude. Additionally birds vision extends into the ultraviolet spectrum. Here in Britain on TV when I was a child, there was a picture of a Blue Tit taken in UV light. As the Blue Tit has a blue crest, hence the name, in UV that crest was like a beacon, and was obviously playing a major part in sexual selection. I seem to remember other birds were shown too, and even in the LBJs detail that was unseen in visible light was revealed. However it was the Blue tit that stuck in my mind as the intensity of the blue varied from bird to bird in UV, but in normal light they looked the same.

While I know that I relatively sharp eyed, I know the daughter of one of my readers, well my only reader, has the eyes of a Golden Eagle and I keep on asking if I could borrow her as a wildlife spotter, but to no avail. So I guess I will have to do my own spotting and misidentification.