The biological study of animals.

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11
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2answers
323 views

Why do crabs spit?

Last year I photographed this juvenile Sally Lightfoot Crab (Grapsus grapsus) 'spitting' (click for larger view): I thought I'd look up more information on this behavior, but couldn't find any ...
2
votes
0answers
24 views

Can you suggest me some books/articles about how female birds indicate receptivity to copulation? [on hold]

Where can I find informations about the topic? I need to find some examples. I also really need this particular information: I know that many female mammals display lordosis behavior that indicate ...
3
votes
0answers
14 views

Extiction of non-mammal Synapsida

I am following M.J. Benton's Vertebrate Palaeontology, which explains how many groups of Synapsida were already extinct in the Mesozoic Era, with one obvious exception being the group of Cynodontia, ...
0
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0answers
15 views

Cells of Zona pellucida

My textbook states: Blastocyst hatches out by lysis of Zona pellucida with the help of the enzyme strypsin, Later the cells of Zona pellucida gradually disappear. We know that Zona pellucida is ...
0
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0answers
16 views

Why do birds in this time of year start singing so early?

I noticed that birds in the beginning of may start singing very early. Earlier than in other months. Why would this be?
0
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0answers
26 views

Chemical colouration and carotenoids [on hold]

How does Carotenoids obtained from diet become an important part of chemical colouration in animals?- What happens after carotenoids enter the body through diet till they cause body colouration? Some ...
0
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0answers
7 views

What did William Harvey discover from experimenting with deer?

On his wikipedia page, I read the following: In particular, Charles' hunting expeditions gave Harvey access to many deer carcasses; it was upon them that Harvey made many observations and ...
3
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1answer
17 views

What is the Cordil that Edward Topsell describes?

In his "History of four-footed beasts and serpents", Edward Topsell describes a "serpent" called Cordil. Since he lists everything that crawls on the ground as a serpent, regardless of being a ...
-1
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0answers
22 views

Is there a logical problem between biology taxonomic categories of domain and kingdom? [on hold]

A tree of life should be diverging right? If the current hierarchy of biological taxonomy is now: "all life, domains, and kingdoms followed by phylum, class, order, family, genus, species." And if ...
0
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0answers
9 views

Tango receptors in worms

Do all parasitic Worms (parasitic platyhelminthes and nematodes) lack tango receptors? I read that the parasitic nematodes lack tango receptors on the surface of their body. Is this true for all the ...
0
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0answers
17 views

Is it legal to send animals for near spaceflight research? [migrated]

For biology purposes, is it legal or not, like using crickets and mouse as subjects to be sent near space (Upper Stratosphere) High Altitude Balloon
5
votes
5answers
2k views

Do male animals visually perceive females as more/less attractive?

If we somehow remove pheromones, do animals experience a phenomenon similar to human "visual beauty" when looking at members of the opposite sex? For example, given a set of 20 female ducks observed ...
6
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2answers
332 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 ...
0
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2answers
27 views

Spatial dimensions for an animal

I'm reading a review paper. They say: The position of an object in head-centered coordinates (that is, relative to an animal's head) can be defined along three axes: the medio-lateral (radial) ...
0
votes
1answer
61 views

How much do crocodiles eat`?

How much do crocodiles eat? The closest I found to an answer was on german wikipedia, where it says that adult nile crocodiles eat "only about 50 full meals a year." While interesting, without knowing ...
4
votes
1answer
52 views

Do ants use something similar to the honey bee “waggle dance” to instruct the rest of the colony where to find a food source?

In the 20 years since we built our home, we've just recently had our first ant infestation. I'm familiar with the fact that ants leave scent trails to find their way back and forth between the ...
0
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0answers
17 views

Body part in motion after decapitation?

I'm sure following video is totally different than of other mammal after their body parts decapitated. In this video apparently, the snake is cut into three pieces. But when we look closer to the ...
3
votes
1answer
45 views

Do animals other than humans dislike food sources that others seem to like?

Humans (especially children...) seem to dislike certain foods or drinks, that other humans seem to like. Common examples are coffee, french cheeses, milk, fish and cabbage. Are there examples of ...
1
vote
1answer
41 views

What nocturnal animal sound am I hearing in the trees in Maine?

Every year, during late summer nights (usually around 9:00 pm) in Maine, I hear a noise coming from high up in the trees. The trees I hear it from are mostly maple or conifer, but where I live there ...
8
votes
3answers
125 views

Do any amphibians start their lives on land?

Most amphibians - at least, all the ones I know of - start their lives in the water (at least, after they hatch). They then spend time maturing before venturing onto land, where they can breed. The ...
7
votes
1answer
92 views

What species of fox is this?

I found this picture of a fox in a news article about arctic foxes in Sweden (source), but I'm not sure whether it is actually an arctic fox. On the one hand, it has white fur, which is the correct ...
5
votes
2answers
84 views

Which of the following lacks DNA?

a) An Enucleated ovum b) Mature RBC c) A mature spermatozoan d) Hair root According to me, there can be 2 answers, a and b because an ovum whose nucleus has been removed lacks DNA. And also, ...
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0answers
31 views

Are there insects who can or try to avoid colliding with raindrops?

Some insects are very fast. Does this mean that they are capable of finding a way through falling raindrops without getting wet? Probably they don't do that at all, because riding on a bike or in a ...
1
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1answer
91 views

Can kit foxes and red foxes produce offspring?

Can a kit fox (Vulpes macrotis) and a red fox (Vulpes vulpes) together produce offspring? Would such a hybrid be fertile?
3
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1answer
69 views

Identification of a small mammal

Could someone help with identification of this small mammal? Is it a possum? A dormouse? It was photographed in Sukhumi botanical garden, in Abkhazia (west of Georgia, on the shores of the black ...
29
votes
2answers
8k views

Who are humans' closest relatives, after primates?

This question here addresses the controversy of whether humans are more closely related to bonobos or chimps. My question is - which group of animals are are closest relatives, beyond primates? Or ...
5
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2answers
251 views

Can animals like squirrels leave “gifts” or tribute for humans?

I've heard anecdotal reports of squirrels bringing up gifts to a person's house after that person left out food for them. Sounds bizzare and unbelievable, until I actually saw some kind of a nut right ...
1
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1answer
40 views

Do camels have nucleated RBCs or enucleated RBCs?

Most mammals have enucleated RBCs as an adaptation to facilitate the transport of oxygen. My text says that camels and llamas are exceptions to these. I was wondering why they are exceptions, and the ...
6
votes
2answers
521 views

What makes an animal/species suitable for domestication/training?

Humans have domesticated all manner of creatures during the course of their civilization - dogs, horses, several types of cattle, varieties of birds, and perhaps others too. A prerequisite for an ...
6
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3answers
275 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?
0
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1answer
20 views

How many cells does the hermaphrodite version of Caenorhabditis elegans have? [closed]

Wikipedia states: The male C. elegans, for example, has 1031 cells How many cells does the female version have?
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1answer
33 views

How to compare diversity between different ecosystems?

I've used the Shannon Wiener Diversity Index for a single ecosystem (species as categorical variables). Do you know any alternative indices, especially ones that compare diversity between different ...
-2
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0answers
44 views

Animal Diversity Character State Matrix

i Need help wit developing a character matrix for all the kingdom animalia. i have spent many days trying to figure this out, but seem to get confused and lost.
3
votes
1answer
69 views

Has the human body the greatest total length of nerves of all animals?

I've read that a human body contains about 150,000-180,000 km (Pakkenberg et al., 1997; 2003) of nerve wiring in the whole body. But does this length increase with the size of the animal? For example, ...
4
votes
1answer
76 views

Species identification - greenish blue ocean worm (nudibranch?) in Perhentian Islands, Malaysia

We found this on a beach at the Perhentian Islands, Malaysia in March, 2016 and cannot identify it. It's some sort of worm-type creature with many legs and bluish back about 15cm long. The legs ...
1
vote
1answer
27 views

What do red ants secrete while marching in a line, one after the other?

Red ants often move in a group, and seem to follow a trail one after the other. Once, I rubbed a part of the path along which they were moving and surprisingly found that the successive ants roaming ...
12
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1answer
6k views

How many mice are on the Earth?

We are 7 billion human beings on the Earth. But how many mice are there? How would you estimate such a number?
11
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3answers
524 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?
1
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1answer
50 views

What are these curious cetaceans?

At the beginning of the superb documentary film “Un jardin d’Eden sous les mers” (“A garden of Eden under the seas”) [1], we see a group of curious cetaceans. At about 1 min. What are these ...
34
votes
2answers
3k views

Do homing pigeons fly straight home or follow certain “highways”?

Homing pigeons (Columba livia) have been prized for their navigational abilities for thousands of years. They’ve served as messengers during war, as a means of long-distance communication, and as ...
-2
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1answer
80 views

What happens to a snail if we cut off its antennae?

First off, I don't know why snails have antennas. Are they eyes? And what if we cut those antennae off? If they are like eyes, could a blind snail survive somehow?
2
votes
1answer
139 views

What is the scientific and common name of this bug?

Captured this under my stereo microscope. Much beautiful than appearing on my camera sensor. Can someone help me identify it and explore more? Also is it having a compound eye ? Location: New ...
1
vote
1answer
36 views

Why can one swim longer underwater by blowing out air?

I am a human. I take a deep breath. I swim underwater... After some time, I need to blow out some air. I blow out some air... By doing so, I can swim underwater longer. Blowing out some air gives me ...
11
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2answers
104 views

Skull mystery on beach

The skull was found on a beach on the Sechelt inlet on Canada's pacific coast. A marine environment. What species is this skull from?
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0answers
34 views

Do other animals have similar blood types to humans? [duplicate]

I am interested to know if there are any animals having blood groups similar to human blood groups? Is it possible to transfuse blood between humans and those animals?
3
votes
2answers
312 views

Can someone identify this bird?

We recently found a nest in the back garden and a little bird inside. Can you help us identify it? The nest is quite small like the bird so we are wondering whether this is the parent or a baby chick. ...
4
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0answers
25 views

Is the knee locking mechanism present in animals?

We study in human anatomy that when the knee is in full extension, the femur slightly medially rotates on the tibia to lock the knee joint in place. This reduces the work required to be done by the ...
8
votes
1answer
72 views

Cockroach-like insect identification

I just saw an insect in my room, and I have never seen anything like it ever before. I captured a photo, please see if you can identify it. It has got quite unique colours on its exodermis and it has ...
48
votes
4answers
3k views

Why do smaller mammals move intermittently?

I was watching a nice little video on youtube but couldn't help but notice how snappy smaller animals such as rats and chipmunks move. By snappy I mean how the animal moves in almost discrete states ...
7
votes
1answer
1k views

What produces the strong odor of decaying dead animals?

Are there specific chemicals responsible for producing the strong, putrid odor that is present after an animal deceases? Also, how long does this odor last?