Dolphins wave weed to attract a mate
While men might try flowers, smart clothes or cars to impress the opposite sex, male Amazon river dolphins carry weed.
Object-carrying has been reported throughout the dolphin's range in Brazil, Venezuela and Bolivia, but what had been thought to be play behaviour now appears - exceptionally among mammals - to have a sexual function.
Tony Martin of the British Antarctic Survey in Cambridge, UK, and Vera da Silva of the National Institute of Amazonian Research in Amazonas, Brazil, have studied the dolphins for three years in the Brazilian Amazon and are now convinced it is a sexual display. Only humans and chimps do anything remotely similar, says Martin. "It's so unusual that many of my colleagues were sceptical when I first suggested the idea, but now I think the evidence is overwhelming," he says.
My comment: Isn't it weird to hear human, chimp and dolphin in one sentence. Ok, not weird, interesting. I think we're finally starting to understand the complexity of other species and that could make us understand, we really are not the only intelligent ones around.
Chimps outperform humans at memory task
Young chimps can beat adult humans in a task involving remembering numbers, reveals a new study. It is the first time chimps – and young ones, at that – have outperformed humans at a cognitive task.
And the finding may add weight to a theory about the evolution of language in humans, say the researchers.
Three adult female chimps, their three 5-year-old offspring, and university student volunteers were tested on their ability to memorise the numbers 1 to 9 appearing at random locations on a touchscreen monitor.
The chimps had previously been taught the ascending order of the numbers. Using an ability akin to photographic memory, the young chimps were able to memorise the location of the numerals with better accuracy than humans performing the same task.
During the test, the numerals appeared on the screen for 650, 430 or 210 milliseconds, and were then replaced by blank white squares.
While the adult chimps were able to remember the location of the numbers in the correct order with the same or worse ability as the humans, the three adolescent chimps outperformed the humans.
The youngsters easily remembered the locations, even at the shortest duration, which does not leave enough time for the eye to move and scan the screen. This suggests that they use a kind of eidetic or photographic memory.
In rare cases, human children have a kind of photographic memory like that shown by the young chimps, but it disappears with age, says Tetsuro Matsuzawa, at the primate research institute at Kyoto University, Japan, who led the study. (See a video library of chimp cognition.)
He suggests that early humans lost the skill as we acquired other memory-related skills such as representation and hierarchical organisation. “In the course of evolution we humans lost it, but acquired a new skill of symbolisation – in other words, language,” he says. “We had to lose some function to get a new function.”
The finding challenges human assumptions about our uniqueness, and should make us think harder about ourselves in relation to other animals, says anthropologist Jill Pruetz of Iowa State University, Ames, US.
“Observing that other species can outperform us on tasks that we assume we excel at is a bit humbling,” she says. “Rather than taking such findings as a rare example or a fluke, we should incorporate this knowledge into a mindset that acknowledges that chimpanzees – and probably other species – share aspects of what we think of as uniquely human intelligence.”Matsuzawa emphasises that the chimps in the study are by no means special – all chimps can perform like this, he says. “We underestimate chimpanzee intelligence,” he says. “We are 98.77% chimpanzee. We are their evolutionary neighbours.”
My comment: Continuing the point of the previous comment, maybe those discoveries are just preparing us for the real finding-a specie that is smarter than us. We all know that would be quite shocking, especially for some religious fanatics, but not only to them-we all assume we're unique in one way or another. What happens when another unique someone claims its place in our Universe? Can we accept it and admit it in our World, or we're likely to feel threatened and try to kill it? Now, those are pretty far-fetched of course, but for me, it is important not only to study the Nature, but also to study ourselves and adapt to what Nature shows us. Who are we to decide whether language and symbols are more important than other forms of intelligence? Yeah, for sure they are more useful for us, but it could be different for other specie- for example, if there is natural telepathy and collective memory, why would that specie need a language? Nothing. But that wouldn't make it less intelligent than us. Just different.
Picture-sorting dogs show human-like thought
Next time you sort through your holiday photos, maybe your dog could lend a hand. It seems dogs can place photographs into categories the same way humans do, an ability previously identified only in birds and primates.
Friederike Range at the University of Vienna, Austria, and colleagues trained dogs to distinguish photographs that depicted dogs from those that did not. "We know they can categorise 'food' or 'enemies' from experience," says Range, "but this is the first time we've taught them an abstract concept - 'a dog' - and shown they can transfer this knowledge to a new situation."
In the training phase, four dogs were simultaneously shown photographs of a landscape and of a dog, and were rewarded if they selected the latter using a paw-operated computer touch-screen. When the computer-savvy dogs were shown unfamiliar landscape and dog photos they continued to identify those containing dogs. And when shown an unfamiliar dog superimposed on a landscape used in the training phase, they were still able to pick it out in preference to an image of just a landscape, showing that they could distinguish a dog by its features (Animal Cognition, DOI: 10.1007/s10071-007-0123-2).
"We are starting to see that dogs have some good reasoning abilities," says Range. "I hope this might impact how we treat them at home."
My comment:As a dog-owner I can easily tell you dogs are VERY intelligent. We would like to underestimate them, but we're wrong. I spend a lot of time with my dog and I simply can see the way he things in many occasions. He does think and he does understand very often what's going on and why it's going on. Of course, I often have no idea what he makes of an event, but in any case, we have much to learn about the capacity and capability of dogs' brains.