The biological study of animals.

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Why are there no wheeled animals?

In physics, "almost everything is already discovered, and all that remains is to fill a few unimportant holes." (See Jolly.) Therefore, on Physics SE, people are veering off into different directions: ...
4
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1answer
111 views

How do animals handle light refraction in different media?

For a human, when diving underwater, everything is blurry because of the water's different refractive index compared to that of air, which we are accustomed to. How do animals, like turtles, seals or ...
12
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1answer
94 views

Help identifying what this is in Crayfish gills?

this is my first time posting here. I was in my Zoology lab doing a dissection on a Crayfish when I noticed these hairlike structures within the gills. They were very "snappy" and fine, and would ...
3
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1answer
23 views

Why are killer whales found in the Gulf of Mexico smaller than ones found in the Pacific?

I recently found out that there are killer whales that live in the Gulf of Mexico, but they are smaller than killer whales that are commonly found in the Pacific Ocean. Why is it they are smaller in ...
2
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1answer
24 views

Cysticercoids of Eucestoda

I have found the following pictures representing cysticercoids of Eucestoda. If I correctly understand the right part of the picture, I would say that the development of the scolex is portrayed on ...
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2answers
65 views

Horns in animals and birds [closed]

Are there any carnivores with horns (whether extinct or currently alive)? Do any flying creatures have horns? By horns I mean horn like structure.
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2answers
1k views

How do birds deal with their eyes drying out at high speeds?

My eyes tear up when cycling at 15 mph, which is nothing compared to bird airspeeds. Do birds continuously produce lots of tears and blink a lot, or do the eyes self-moisturize from the inside ...
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0answers
59 views

How did birds become so intelligent?

I have seen a Discovery Channel video of a bird throwing stones in a pot to raise the water level so it is able to reach and drink it. A similar experiment in this paper from Current Biology shows ...
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0answers
21 views

Founders of Cnidarian colony

I know that colonial Cnidaria enlarge their colony by the means of asexual reproduction and sexual and asexual reproduction can originate individuals that will be part of other colonies. ...
16
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2answers
661 views

Do plant-animal cross races exist?

Plants and animals have the following distinct properties: Plants live from solar energy by photosynthesis, they use solar energy to make sugar and oxygen out of carbon dioxide, which gives them ...
8
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1answer
71 views

What will happen if a scorpion pierces itself?

If a scorpion pierces itself, will it die or immune to its poison? If it produces the venom its blood should be immune to itself poison.
2
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1answer
25 views

How animals know which is carnivorous and herbivorous?

Deer ran away from tiger or cheetah, but not from giraffe or zebra. where did deer learn this? How animals know which is carnivorous and herbivorous?
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1answer
69 views

Why are butterflies drinking blood?

According to this video, butterflies sometimes drink blood. Do they have the organs necessary to digest blood? I thought they eat only salts and nectar, which are easy to digest compared to proteins. ...
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3answers
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Do cows produce milk excessively?

Do cows produce more milk than it is required for their calves? It seems like cows are able to provide milk all the time (all year around). Is it so? Or do they, like other mammals, produce milk only ...
5
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1answer
49 views

(Why) are polar bears more common in Labrador than in southern Greenland?

The Labrador Sea is between Greenland, Labrador, and Qikiqtaaluk: Map source. A Greenlandic source on polar bears states: In Greenland the polar bear lives and breeds in the northernmost parts ...
0
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1answer
52 views

Why do insects avoid being on their back?

I have noticed that when insects are placed on their backs, they tend to turn themselves over quickly or else appear to be in distress. Is there a physiologic, anatomic, or adaptive reason why supine ...
3
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1answer
60 views

Why does cucumber skin kill ants?

I recently read that cucumber skin is an effective repellent for some ants: Set out cucumber peels or slices in the kitchen or at the ants' point of entry. Many ants have a natural aversion to ...
7
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2answers
67 views

Do other animals have different blood types?

Humans have the ABO and Rhesus blood typing systems. I have two questions about it: Why have we evolved these blood types? Do other animals have different blood types as well?
2
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1answer
37 views

Detailed mechanism of the cause of diabetes mellitus type 1?

I have read in some texts that diabetes mellitus type 1 is caused by degeneration of beta cells due to our body's own immune reaction.Is it true? Can you explain further how are such types of immune ...
15
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3answers
714 views

Are there cats with black skin?

Some mammals can have a black, pink or spotted skin, depending on race - see for example humans or pigs. But I recently learned that this is not the case with mice. Even black furred mice have pink ...
3
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2answers
143 views

Are these cats calico?

Calico cats are cats that have 3 fur colors and are always female or males two X chromosomes. I've seen many cats that will have 2 fur colors (one of them is usually white) and another, third, color ...
4
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1answer
20k views

Why are (some) cats attracted by bleach?

(Sorry if this question is only partly biological) I have noticed that several cats (including the one that keeps sleeping in my house), are fond of the odor of bleach (eau de Javel) and chlorine. ...
12
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1answer
5k views

Fish “coming back to life” after being frozen

I've encountered a clip on Youtube showing a goldfish thrown in liquid nitrogen and immediately after to normal water and swimming normally. In the explanation to the clip it says: For everyone ...
2
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2answers
227 views

How can we know or measure pain in animals?

Is there any standard way to know how much pain an animal feels when it gets hurt like when a bird loses it's wing or hen when killed etc. All pain sensation points? Hey I'm new to biology. :)
4
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2answers
79 views

What is called the “area size that an animal usually lives in”?

What is called the "area size that an animal usually lives in" or "needs for a normal life"? Is there any specific term?
2
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1answer
58 views

I found these skulls in a old bottle in the woods. Can you tell me what they are?

Can you help me identify these skulls I found in an old bottle in the woods?
4
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1answer
56 views

How can a drone be male?

A drone bee is male and is the product of only a queen bee. How is it that the drone bee can be male. I know that a drone is produced by an unfertilized egg, but this does not explain where the two X ...
8
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2answers
112 views

What is a group of tortoises called?

This post at Mental Floss stated that a group of tortoises is called a 'Creep'. I had never heard of that before, and in trying to find the references for the name, I was surprised that I couldn't ...
2
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2answers
63 views

Do animals exist which have great vision, but see only grayscale?

In computer vision the color information is often discarded, as most object recognition tasks seem to work just as well on the greyscale image (even better, because there is less unnecessary ...
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1answer
39 views

Can anyone identify the worm in this video clip?

My wife came across this youtube clip of a spider and a worm. Can anyone identify at least the phylum?
7
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2answers
2k views

Why animals can move and plants cannot in general?

To clarify, I think the answer should be able to explain: What are animals? What are plants? What's the difference between animals and plants (How do biologists differentiate them, if they ...
3
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1answer
106 views

How do cats survive falling from great heights?

Among mammals, cats are able to land safely when falling from great heights. For example, when compared to dogs or humans they can survive drops from relative large heights. How do they manage? A ...
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1answer
37 views
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1answer
46 views

Was Earth's atmosphere more buoyant in the prehistoric era then today?

The mass and size of the dinosaurs and prehistoric insects continues to amaze me. I read from an earlier post that oxygen was more abundant during the prehistoric era. However supporting the weight ...
12
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1answer
136 views

Why are fly not scared when landing on a monitor with changing graphics?

I have been wondering why would insects in general, not be scared when important changes happen on your monitor where they have landed... If you move even just a finger, they are scared to death and ...
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5answers
1k views

Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them? ...
10
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2answers
137 views

Can canines communicate with each other using gaze direction?

After researching why humans have white scleras when most primates have dark scleras, I stumbled upon the cooperative eye hypothesis. It proposed that white scleras may have evolved on behalf that it ...
6
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1answer
58 views

Chickens roosting, is it sleep or torpor?

At night when they roost, do chickens experience a state of sleep (meaning do they move from NREM1 to NREM2, NREM3 and REM) or are they in a state of torpor (reduced metabolic rate and decreased ...
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3answers
3k views

How much energy does a lion contain? [closed]

I was looking into the following problem: Obviously, the solution lies in how much energy either can output per unit of time. The total energy output of the sun is $3.8×10^{26} \frac{J}{s}$. The ...
3
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3answers
950 views

Which organs do cats not eat on their prey?

My female cat is a very active hunter and brings me her prey daily. Except for shrews and birds, she always eats them entirely. This afternoon she brought me this: It was quite large (maybe ...
12
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1answer
145 views

Do species other than humans have distinct daily feeding patterns?

I have a general interest in complex adaptive systems and I have found that nature and the organisms within it is a perfect natural case of a rich adaptive system with a lot of possibilities for ...
7
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1answer
848 views

Facultative Cannibalism?

I heard about Larger cats eating the cubs. Is it some kind of facultative cannibalism or they can eat there own kind like that? What are the facultative cannibalism present in animal kingdom? What ...
6
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3answers
365 views

How many cells does the smallest animal have?

Note: question rewritten to prevent misunderstanding and make it more answerable I know that some small animals like C. elegans display surprising sophistication with a very small number of cells. ...
4
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2answers
116 views

Can I force evolution in a group of cells by removing all the smaller cells?

I actually have algae growing in water in a container. I was thinking if it was possible to filter the water so that all the small cells will be filtered out and only the bigger ones will remain to ...
11
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4answers
3k views

Why do parasites sometimes kill their hosts?

It's bothered me for a while now. I understand why a parasitoid would do this, as it only temporarily requires the host, and that not all parasites kill their hosts. There seems to be no evolutionary ...
3
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1answer
37 views

Why are canines not nauseated by similar foodstuffs/state of decay as human beings?

I am continually surprised at the items my pet dog is willing to ingest. I understand part of the consumption is driven by nutritional instincts (licking salty liquids such as sweat) or nurturing ...
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0answers
52 views

The skin color of bonobos

Why is that bonobos skin color on the areas not covered by hair are dark throughout life unlike the chimpanzee?
0
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0answers
60 views

How important is the womb's environment?

- Background - Talking about one phenotypic trait, the total phenotypic variance $V_p$ is decomposed into genetic and environmental variance for this trait, represented by the symbols $V_G$ and $V_E$ ...
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3answers
152 views

Are domesticated animals really “more intelligent,” or is that a myth/misunderstanding?

Often do I hear people speaking of how the domestic house cats are more friendly, less ferocious, less savage-like, and smarter and/or than their distinct but equivalent feline-species friends, like ...
2
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1answer
485 views

Why are urban birds still scared of humans?

I understand that animals are naturally scared of humans because we basically slaughtered every living thing we found in our way for millennia. How long does it take for them to genetically 'forget' ...