h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: The War of the Crows - A2182088
Author: Gnomon [Come to the London January Meet. See A3098991 - Lost 3.8 kg in 8 weeks] - U151503

I got an expert ecologist to check this out, and he think's it's OK, so I'm submitting it for your approval.

Excellent! The paragraph on Dr Gause is worth an entry in itself! Very close parallels to the decline of the Neanderthals.

Hooded crows are quite smart birds that appear to be keenly adapted to seashore life - they have figured out how to eat shellfish by lifting them up into the air and dropping them on rocks from quite a height.

Great article.

Woodpigeon

Where do North American crows fit into the picture, just out of curiousity? We have both crows (all black) and ravens around here (as well as magpies and various jays, also corvids) but I've never heard mention of anything like the hooded crows here.

oh. apparently we have something called Corvus brachyrhynchos.

This is a great little article. But I have one question: if they're so bloody similar, why did they speciate in the first place?

At the seaside here is a village called Cadzand, near Belgium, and there live a lot of crows, especially a colony of jackdaws! There are carrion crows and and and ... STORKS as well! No hooded crows though. Cannot remember ever having seen one.

GF Gause was a Russian scientist who study microscropic > who studied

I don't know whether this is at all enlightening but my Observer's Book of Birds says that '[they] are regarded as races of the same species'.

Mnemonic: How can you telkl the diffrence between a crow and a rook?

Answer: If you see a rook on ots own it's a crow. If you see several crows together, they're rooks.

Crows are usually in pairs, two of them together. If it's on its own, it either lost its mate or hasn't found one yet.

Down in South Wales, where I come from, there are thousands of jackdaws. I have never seen as many in any other part of the country. I also once saw *ten* magpies together in a field.

Magpies seem to be particularly common in Ireland now, which is strange because they were rare fifty years ago. I've seen 25 magpies together.

Well, this book will probably give the answer:
http://www.amazon.co.uk/exec/obidos/ASIN/0715632973/026-5732655-8552467

Good work; I'm sure they are seperate species though I'm more of a heathland guy myself! I love any of these slightly quirk ecological entries.

Hi BigAl! Older books list the two as different races of a single species, but recent research shows that they are actually separate species.

Any references for this recent work? All my books give the two as sub-species (even BWP), but then I have nothing later than 1994.

The Royal Society for the Preservation of Birds:

http://www.rspb.org.uk/birds/guide/c/carrioncrow/index.asp

Thanks, although I still wonder how they determine these things. DNA?

The two birds look so different that you wonder why they were ever thought to be a single species anyway. They do interbreed occasionally, but bird hybrids are fairly common.

Ducks are apparently pretty fecund. The ruddy duck is a sod for playing away: A663004

Nowadays I'm certain it would be DNA. However, I guess that the alternative would be by careful observation of behaviour. The definition of 'species' is an organism that can breed with another to produce fertile offspring. Hence if these two crows were the same species, one would expect hybrids to be common along their common geographical boundaries.

Just a quick comment on the title, it's exiting but not very accurate.
There is no war going on between the two species. They don't share the same territory, that's all, isn't it? Where I live the carrion crows share their territory with jackdaws, ravens any kind of crow, really. There is no question of a war going on between the different members of the crow family.