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15

Handedness has been studied in several different species of toads. As basal tetrapods, the authors argue that these taxa are unlikely to be influenced by human hand dominance and are thus a better model for studying the evolution of handedness. Bisazza et al. (1997) studied "pawedness" in Bufo bufo, B. viridis, and B. marinus in wild-caught animals by ...


11

Cats and dogs can both view tv screens & monitors ... though their viewing experience is a little different to ours thanks to differences in cone structure leaving them color blind and giving low acuity. Both species have lower levels of color vision than humans. Cats see slightly more color (in the blue green and yellow end of the spectrum) than dogs ...


11

Yes. Menopause is common for long-lived mammals. For instance, in the wild, killer whales go in a sort of menopause as reported in 2009 by Ward et al. Front Zool. 2009 Feb 3;6:4. So it is not due to captivity. According to a Nature review, reproductive cessation has also been documented in non-human primates, rodents, whales, dogs, rabbits, elephants and ...


10

The female stood with the tail held sharply to one side, and the quills on the back lying very flat. The male stood on his hind legs, while the front legs grasped the sides of the female. There was no repetition of the act. The male's urethra is 115-120 mm long, and his penis is 75 mm, so the he doesn't need to be as close to the female as one ...


9

As both @Rory M and @Alexander Galkin suggest, there are various non-visual mating behaviors to allow these species to select mates and also allow taxonomists and researchers to identify these species. And they hit on the two major ones, courtship rituals (mating calls, throat bulging, dancing) and pheromones. Let's have a look at some two examples: The ...


8

Limiting the conversation to mammals, and taking relative brain size as a proxy for intelligence (which, of course is not necessarily "true", but at least is quantifiable), the answer is yes: body-size relative brain size correlates with body-size relative longevity in mammals. using a global database of 493 species, we provide evidence showing that ...


7

"How come most animals never seem to evolve over millenia?" I guess the word "seem" in your question should not be disregarded. You seem to assume that cockroaches (or most animals as you say) did not change much the last tens or hundreds thousands of years. But what do you know about that? Have you actually reviewed many research that estimate the rate of ...


6

Having read this article on tool use in Chimpanzees in full, I am inclined to say that if such a term existed then either the article itself or the titles of any of the 30 articles referenced would have included it. Searching a couple of online biological dictionaries and ethology sites hasn't yielded anything either, therefore until someone else points ...


6

I agree with Amory in the sense that the Hamilton's rule is not a rule that apply to each specific individual and explain their behavior (or other traits). The Hamilton's rule describe the direction (and not the dynamic) of how a social trait evolve. $RB>C$ is a simplistic way of looking at Hamilton's rule which might bring you to some confusion. This ...


6

Yes, sub- or satellite colonies are common in many species (see e.g. Hölldobler & Wilson, 1990; Debout et al. 2007), and these are then labelled as polydomous species. Subcolonies can either contain extra queens, but sometimes only contain foraging workers. The purpose can be both to expand foraging grounds or as a pre-stage for colony budding. The ...


5

Yes, it is a common behaviour and is called necromone signaling (Yao et al 2009, see references in paper for many examples), and is probably used to avoid predators, parasites and disease. The chemicals used are often similar (unsaturated fatty acids), and seem to have an old evolutionary history (~400 million years). Many groups of species can also detect ...


5

The author is likely referring to the mechanosensory behavior of bone (reviewed in Huang and Ogawa, 2010; lots of Google Scholar citations). Bone loading produces very tiny mechanical deflections (strain) which are translated into biochemical signals that promote bone growth through the action of osteoblasts. Burger and Klein-Nuland (1999) review possible ...


5

Mantis shrimp use their first maxillipeds for grooming (maxilliped=modified appendage), which is specialized for this purpose. Details and a picture of the organ can be found in the link. The second maxilliped is their famous specialized organ for striking or spearing prey with enormous force. More about their raptoral appendage, with links to further ...


5

Actually, nesting failure means that nesting trial fail before offspring could even leave the nest. In case of precocial species (where chicks leave nest immediately after hatching, like swans) it means that eggs was destroyed or parents abandoned nest, as @nico point out. In case of altricial birds (offspring stay in nest) nesting failure may also mean that ...


5

Apparently it refers to the inability of nesting the eggs, because the nest was somehow destroyed, or environmental conditions were unfavourable. I found a few examples pointing in this direction: The Trumpeter Swan page on the Yellowstone National Park websites reports that: Nest flooding is the primary cause of nest failure. Egg predation by coyotes, ...


5

You will be hard-pressed to find any scientific data on this question. Psychology in humans is already a difficult study, at times failing to demonstrate results with real scientific rigor. When studying animal psychology, you face another substantial barrier - language. Although some primates have been taught to communicate with sign language, the best of ...


4

The problem is that committing suicide, using the commonplace definition of it, would require an understanding of death. I am sure that an animal can have a basic understanding of the death of others, so far as they realise the difference between a living companion and it's dead body. But if they understand that this lifeless body will never go "back to ...


4

Unlike Terdon I think that you are generally correct in your assertion that animals can swim whereas humans can't (although I'm sure there are exceptions). However, I think his answer contains the real answer: Dogs can't swim as such, they simply do the same motions in the water as they do on land. There is no different action happening, they don't ...


4

While I am not sure I buy your assertion that all mammals know how to swim, I would say that humans are at least as good as dogs when swimming. If you drop a human in water we will instinctively flap around and try too keep our head out of the water in about as elegant a way as a dog. The main problem for humans is panicking. Someone who does not know how to ...


4

As far as I understand it, Hamilton's "rule" isn't really meant to apply individually, it's meant as a way of thinking about kin selection and altruism that can be reduced to individual cases. The reality is that B and C can rarely, if ever, be easily measured or determined. If the two sides were equal then who knows? You'd have to observe it. Presumably ...


3

a) stronger aggressive behaviour only during egg laying c) stronger aggression when egg is first laid than during nest building d) greater aggression during hatching eggs than during nest building These all occur after the stage which determines fitness. Egg laying (a and c) and Egg hatching (d) occur after the male has won the right to mate. ...


3

"Hamilton's rule states that if rB>C then a gene giving altruistic behaviour will increase in frequency in the population." To start here are some examples of how Hamilton's Rule works... In a population of four individuals a pair of adults mate. A first unrelated male (r=0) is genetically coded to help raise their offspring by an allele (selfless) ...


3

Not really my field, but I can point to this review which discusses a couple of different ways in which ants organize their communities: Heinze. 2008. The demise of the standard ant (Hymenoptera: Formicidae) I know that in some species there can be several queens per colony (so more robust to queen deaths). In many species, workers can start laying eggs if ...


3

There has been several major transitions (John Maynard Smith and Eors Szathmary) and systematically there is opportunity for conflict to arise…. and it does! There is conflict along genes within a chromosome (example the Psr gene of Nasonia vitripennis, see R. Trivers and A. Burt Genes in conflict), along chromosome within an individual and along individual ...


3

Do some research on wolves hunting. They certainly have tactics that change depending on the prey that they're hunting, the terrain, danger posed by other members of the prey's herd or family (if any), etc. They're very capable of learning, and use fairly complex communications. They run in packs, live with their mother for a number of years, and have a ...


2

Well, there are certain behaviors that may qualify. The clearest example I know of would be sexual cannibalism, and more specifically (source): The redback spider is one of only two animals to date where the male has been found to actively assist the female in sexual cannibalism. In the process of mating, the much smaller male somersaults to place ...


2

In most species, females are pregnant as often as they can be. Since the availability of sex is rarely a limiting factor, it seems likely that female bonobos are as "always" pregnant as other chimps and socially living primates. The actual rate of pregnancy will be hormonally limited by things such as reduced fertility during lactation and so on.


2

It is not that easy. Off the top of my hat I can try to pinpoint a few fallacies in your theory: Scaling of the body happens in three dimensions and thus to a power law. As such allometric equations have to be applied when dealing with the total amount of substance in the body. Different species have different correlation factors of body mass to total ...


2

Oddly enough it is a bit difficult to find good field studies where the diet of spiders was studied. I have a feeling it's a hard thing to get funding for. Luckily some do exist. Peucetia viridans has been shown to eat from the Chrysididae family and Lepidoptera order, but I didn't find an explicit statement that it ate the larvae out of the caterpillar. ...



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