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Posted: 01-09-2012 07:49 Post subject:

Birds hold 'funerals' for dead
By Matt Walker, Editor, BBC Nature

Some birds, it seems, hold funerals for their dead.
When western scrub jays encounter a dead bird, they call out to one another and stop foraging.
The jays then often fly down to the dead body and gather around it, scientists have discovered.

The behaviour may have evolved to warn other birds of nearby danger, report researchers in California, who have published the findings in the journal Animal Behaviour.

The revelation comes from a study by Teresa Iglesias and colleagues at the University of California, Davis, US.
They conducted experiments, placing a series of objects into residential back yards and observing how western scrub jays in the area reacted.
The objects included different coloured pieces of wood, dead jays, as well as mounted, stuffed jays and great horned owls, simulating the presence of live jays and predators.

The jays reacted indifferently to the wooden objects.
But when they spied a dead bird, they started making alarm calls, warning others long distances away.
The jays then gathered around the dead body, forming large cacophonous aggregations. The calls they made, known as "zeeps", "scolds" and "zeep-scolds", encouraged new jays to attend to the dead.
The jays also stopped foraging for food, a change in behaviour that lasted for over a day.

When the birds were fooled into thinking a predator had arrived, by being exposed to a mounted owl, they also gathered together and made a series of alarm calls.
They also swooped down at the supposed predator, to scare it off. But the jays never swooped at the body of a dead bird.

The birds also occasionally mobbed the stuffed jays; a behaviour they are known to do in the wild when they attack competitors or sick birds.

The fact that the jays didn't react to the wooden objects shows that it is not the novelty of a dead bird appearing that triggers the reaction.
The results show that "without witnessing the struggle and manner of death", the researchers write, the jays see the presence of a dead bird as information to be publicly shared, just as they do the presence of a predator.

Spreading the message that a dead bird is in the area helps safeguard other birds, alerting them to danger, and lowering their risk from whatever killed the original bird in the first place, the researchers say.

Other animals are known to take notice of their dead.
Giraffes and elephants, for example, have been recorded loitering around the body of a recently deceased close relative, raising the idea that animals have a mental concept of death, and may even mourn those that have passed.

http://www.bbc.co.uk/nature/19421217

Posted: 01-09-2012 11:00 Post subject:

"It has been observed (not infrequently) that when a member of the flock perishes, the birds will hold what could be called a “raven funeral” – a 24-hour event marked by raucous outcries."

From A 2007 FT Article about ravens

A quick look online turned up a 2009 Mail article about magpies' funerals.

Bird funerals were observed, iirc, by Victorian naturalists - I've drawn a blank, though on Gilbert White, so far.

But I'd call Who Killed Cock Robin? as witness, if a song can be a witness:

"All the birds of the air fell a sighing and sobbing
When they heard of the death of poor cock robin."

Wikipedia gives an earlier version from 1770

Posted: 19-09-2012 18:54 Post subject:

I witnessed some interesting swan behaviour today: I was walking N on the new Hayle bridge when a swan flew past me and landed on the road!

http://img.photobucket.com/albums/v212/rynner/Swan01_zps170080f9.jpg

Why would it do that? Well, it was landing against the NW wind to lower its ground speed, and it only had to take a few steps before touchdown was complete. In fact, I think that's the first time I've seen a swan land on solid ground.

It then continued to walk N for a while - luckily traffic was light, but this van had to take avoiding action:

http://img.photobucket.com/albums/v212/rynner/Swan02_zps7174a928.jpg

After a while it realised there was no quick way down to the water from there, and it turned around and walked south. I watched the strong ebb tide for a while, and then I realised the swan had found a gap in some safety fencing, and was now on top of the harbour wall on the S side of the waterway, maybe 15 ft above the water. I turned my camera towards it, but it immediately launched itself into the air so I was only able to catch it landing, in typical waterski fashion:

http://img.photobucket.com/albums/v212/rynner/Swan03_zpse753b4f0.jpg

This short glide was parallel to the bridge and thus again into the wind. To the lower left of the pic is part of a rocky ridge that divides the shallow, drying area to the north from the deeper channel in the south, and the flow of the ebbing tide can be seen. The swan almost reached this ridge before stopping.

I began to wonder if the swan had realised it couldn't land across the channel from free flight because it would have been a bit higher, and going faster, and that's why it decided to land on the bridge itself.

Interestingly, there were a couple of swans in the shallows near the N shore, but I imagine that to attempt a landing there on a falling tide would have been risky, because apart from rocks there are a few bits of debris in the area which could severely injure the feet of a waterskiing swan.

http://img.photobucket.com/albums/v212/rynner/Swan04_zps273b5684.jpg

So not only do swans have to know about wind speed and direction, they need to know about the tides and tidal streams. It could be there's a lot going on in that little head!

Since not all swans live by tidal waters, do they learn about tides from their parents, or just pick it up by themselves?

Posted: 19-09-2012 22:19 Post subject:

I'm sure I read somewhere recently that swimming birds learn to do so by being taught by their parents, so I suspect it's much the same mechanism in effect here.

Posted: 12-02-2013 08:51 Post subject:

Dogs understand human perspective, say researchers
By Sean Coughlan, BBC News education correspondent

Dogs are more capable of understanding situations from a human's point of view than has previously been recognised, according to researchers.
They found dogs were four times more likely to steal food they had been forbidden, when lights were turned off so humans in the room could not see.
This suggested the dogs were able to alter their behaviour when they knew their owners' perspective had changed.
The study, published in Animal Cognition, conducted tests on 84 dogs.

The experiments had been trying to find whether dogs could adapt their behaviour in response to the changed circumstances of their human owners.
It wanted to see if dogs had a "flexible understanding" that could show they understood the viewpoint of a human.

It found that when the lights were turned off, dogs in a room with their human owners were much more likely to disobey and steal forbidden food.
The study says it is "unlikely that the dogs simply forgot that the human was in the room" when there was no light. Instead it seems as though the dogs were able to differentiate between when the human was unable or able to see them.

The experiments had been designed with enough variations to avoid false associations - such as dogs beginning to associate sudden darkness with someone giving them food, researchers said.
Dr Juliane Kaminski, from the University of Portsmouth's psychology department, said the study was "incredible because it implies dogs understand the human can't see them, meaning they might understand the human perspective".

This could also be important in understanding the capacities of dogs that have to interact closely with humans, such as guide dogs for the blind and sniffer dogs.

Previous studies have suggested that although humans might think that they can recognise different expressions on their dogs' faces, this is often inaccurate and a projection of human emotions.
"Humans constantly attribute certain qualities and emotions to other living things. We know that our own dog is clever or sensitive, but that's us thinking, not them," said Dr Kaminski.

"These results suggest humans might be right, where dogs are concerned, but we still can't be completely sure if the results mean dogs have a truly flexible understanding of the mind and others' minds. It has always been assumed only humans had this ability."

http://www.bbc.co.uk/news/education-21411249

Posted: 19-02-2013 21:28 Post subject:

This might have been covered somewhere in the 5 pages, but I've always wondered....

How do certain species of animals know to group up with the same exact species. For example, 2 clownfish. How in gods name does one clownfish know that he is a clownfish? certainly it can't see itself, so why does it team up with the other clownfish? Or 2 silver minnows, same deal. 2 finches, etc. A finch will always hang out with other finches instead of a parrot, etc....

Dogs I can understand. It's pretty obvious they both have 4 legs and tails, are at the same eye level, etc. But what about so many others?

Posted: 19-02-2013 22:52 Post subject:

Posted: 20-02-2013 00:50 Post subject:

Seeimg as how clownfish have grown up with other clownfish they doubtless know who their friends are. Plus sight is only one of an animal's senses.

Posted: 20-02-2013 12:40 Post subject:

A male duck will only mate with a female that looks like his mother, if you put a duck egg in the nest of different species the male duck will not mate with females of his own species.