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2

While their work was in the cat rather than the dog, your starting point should be the work of Hubel and Wiesel. They are the indisputable pioneers for vision research in general. They won the Nobel Prize in 1981 for Physiology and Medicine. See their Wikipedia entries (Hubel and Wiesel), the original 1962 paper, their popular press book, the Nobel Prize ...


3

Color vision was shown to be dichromatic (sensitivity to two color peaks) by Neitz et al. (1989). For a broader review of color vision of mammals, see Jacobs (1993). Literature Cited Jacobs, G.H. 1993. The distribution and nature of colour vision among the mammals. Biological Reviews 68: 413-471. Neitz, J. et al. 1989. Color vision in the dog. Visual ...


1

Yes. Once secreted the shell cannot increase in size, so that the growth of the body is accompanied by continuous growth of the shell, i.e. by the gradual increase in the number of the whorls. This also means that the topmost whorls are the oldest and the aperture marks the front of the new shell.


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Biology is not deterministic. Traits like this have variable expressivity. A phenotype with 100% expression in a population with an allele is said to have complete penetrance. There is no gene which could specify a single blood vessel pattern that could have complete penetrance. Variable expressivity means the same genes yield a spectrum of forms of the ...


2

The answer is... basically none. The variability is high, and can also happen in the macroscopic range. If you want a quick-and-dirty idea of the fraction of the population presenting a certain variability in humans, I would suggest a good anatomy atlas or manual. A good resource would be Gray's Anatomy (the book, not the soap ;-). Apart from that, @Armatus ...


3

Indeed a very good question. I'm afraid it might remain without a proper anatomy-based answer, but my intuition would tend towards agreeing with "the smaller you get, the more deviation you'll find". Or rather, I would expect the same principle as in conservation of genetic patterns to apply here: the more central a tissue structure is to survival, i.e. the ...


4

That is a threat face. Barbary macaque threat faces often appear with a brow raise, lowered head, and an o-shaped mouth, sometimes with and sometimes without a vocalization. Given the context you described it is not surprising the girl received a threat. *Based on personal research experience


4

It looks like it is trying too threat. Source: Individual differences in scanpaths correspond with serotonin transporter genotype and behavioral phenotype in rhesus monkeys (Macaca mulatta)


11

Interestingly there is a inverse negative correlation between heart rate and life span, meaning the faster your heart rate is, the shorter is your lifespan. See this figure (from the paper 2 cited below): When the authors plotted the approximately total heartbeats vs. the lifespan, the amount of total heartbeats was in a pretty narrow corridor: So it ...


6

After some more searching, I think stumbled across the answer. It appears to be an… Eriophora ravilla: Source BugGuide.net. This species appears to have quite a diverse range of colors, and even thought I haven't found one that quite matches mine, the other similarities (the large abdomen, the stripe down the back, the four 'dimples', and the ...


2

I'm not a medical professional, so this isn't exhaustive or guaranteed 100% accurate: You can live a (*mostly) normal life without your: appendix tonsils spleen gallbladder pancreas portions of your liver (pieces can be removed and it will regenerate) portions of your small or large intestines both lungs (one is needed) both kidneys (one is needed) ...


4

Insomnia most certainly occurs in other animals. One interesting example is the case of insomnia in Drosophila melanogaster. In this study 3 day old male and female flies that demonstrated reduced sleep time were crossed together over 60 generations to create flies insomnia-like (ins-l) that sleep less than 60 minutes a day compared to 800 min a day in their ...


2

Cattles actually hate shrubs which are very tough to break and tasteless(for a cow). Some plants they won't touch are: Lantana urticoides (West Indian shrub verbena), Malvaviscus arboreus var.drummondii (wax mallow) Rhus copallinum (winged sumac) Viburnum acerifolium (mapleleaf viburnum). Morella cerifera (wax myrtle) Ilex vomitoria (yaupon). Source: ...


1

I will Suggest: Selective Breeding in Aquaculture: An Introduction Authors: Trygve Gjedrem, Matthew Baranski ISBN: 978-90-481-2772-6 (Print) 978-90-481-2773-3 (Online)


3

As the previous answers clarify, all organisms have heritable traits that may be manipulated through selective breeding. It is the pragmatics that can be prohibitively challenging. From an (zoo)archaeological point of view, few animals have actually been domesticated, and only recently in our species' history. The dog is an unusual case, perhaps domesticated ...


1

Nictitating membrane (inner eyelid) of sharks can cover sharks eye as it moves from the upper to the lower eye lid (http://en.wikipedia.org/wiki/Nictitating_membrane).


1

Actaully there are quite a few animals which actually moves there lower eyelids: Most of the birds Reptiles(Except Snake) Amphibians


0

Many examples of animals which have more difficulty maintaining their population size than humans exist. This is partially why some species go extinct. The Tasmanian Devil is at high risk for extinction from a genetic predisposition for cancer onset by infection. Your premise that humans are unhealthy is not sound. Humans are long lived, genetically diverse ...


2

As everybody, I don't fully understand your question. Can you please add your definition of domestication? Would you consider domestication as soon as human can select for heritable traits? If yes, then the question may be split in two: Do all animal populations have heritable traits? Yes! But Depending on what kind of traits you want to consider no ...


14

It's definitely a bird pelvis (synsacrum). Based on the size (~30 cm), it came from a very large bird. Unfortunately, comparative images of bird pelves are rare on the internet. Some possibilities (large birds of Sweden possibly found on the coast): Great northern loon Golden eagle Common crane A loon skeleton (from ...


5

This is a story I have been told as well when I was a kid. Usually this is related to the foreign smell that the humans leave on the chick. However, this seems to be an urban legend, as birds have not a great sense of smell. Snopes says about this: However, Mother birds will not reject their babies because they smell human scent on them, nor will ...


2

I'm putting my bets on the Pistol Shrimp (Alpheus heterochaelis) They can be grow 3cm to 5cm Long which is incredibly small for the amount of db it can create. Their sound is a by-product of their large claw snapping shut and creating a cavitation bubble that creates a lot of pressure and then produces up to a recorded 218 Decibels. This "click" or "pop" of ...


2

Reason for Migrating Birds: Migrating for a Meal Food scarcity: If birds will stay and eat all the bees they find, there will be no bees to feed on for the next generation. So, they fly away to take advantage of these places where there is abundance of food. And when the insects or replenish they come back. Migrating for Family Flocks of bird can be easy ...


1

It could be Wood Mouse(Apodemus sylvaticus). Courtesy : redbubble.com


4

I will go with lesser water boatman(Micronecta scholtzi). The loudest of everything as well as small. Size: 0.07-inch (2-millimeter) Produces the highest sound by size ratio. It's sound is almost equivalent to pounding jackhammer at two feet distance. Source and Image Courtesy: So Small, So Loud: Extremely High Sound Pressure Level from a Pygmy ...


3

Could not fit in a comment… I don't quite know how to answer. I think that the only answer one could give is why not?. Various mechanisms may evolve under different life-history, different environment, different ecological strategy, different mutations occuring,.. In some species (including some amphibians) the evolution of sex determination system is ...


11

Lions Lions are a classical example of cannibalism. To understand why this occurs we have to understand their mating system. Males have harem of females and males fight in order to access a harem (Note: females may also take part in the battle depending of which male they prefer). When a male takes over a new harem, he may kill the youngs of the previous ...


1

As far as getting inside, they are small, and they can get in through openings you don't notice, or just sneak in when you open the door.



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