The biological study of animals.

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1answer
26 views

Is there evidence to suggest that sharks from prehistoric times live in the deep of the oceans?

I've had friends see the boat and giant teeth of a giant shark attack of a boat in Japan. (Teeth larger than a great white). [I can't find anything about this on the Internet]. In addition, this ...
-1
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0answers
22 views

Why people have less hair than other primates?

Well as you can figure out, most primates such as monkeys, gorillas and chimpanzees, have all their body covered with fur. As we know they are evolutional "relatives" to us humans, but we dont have ...
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2answers
32 views

Predator prey interaction [on hold]

I went through a line in my textbook which read: "But for predators, prey species could achieve very high population densities and cause ecosystem instability." I was not able to understand the ...
3
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1answer
17 views

Could a large constrictor kill a small animal?

According to this article there was a python whose body circumference was 85cm. This means its diameter was 27cm. Would it be possible for this snake to constrict animals that are about the same ...
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0answers
15 views

How the Phereoeca uterella (casebearer) is formed? [on hold]

Does anyone know how the Phereoeca uterella known as the casebearer is formed or born?
4
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2answers
69 views

Do any terrestrial herbivores use auditory crypsis for predator avoidance? [on hold]

Some terrestrial predators "stalk" their prey: they sneak up on it slowly, maintaining a low profile, while keeping as close to silent as possible. This makes sense from an evolutionary perspective: ...
3
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1answer
117 views

Why Crocodiles don't eat Hippos?

I have been following documentaries about crocodiles and amazingly, crocodiles and hippos apparently seem to live happily in the same pond together without attacking each other. Why is it so? Like ...
5
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2answers
53 views

Insect making continuous sound in summers

In deciduous to tropical-deciduous forests and residential places with such vegetation I have found this insect to make continuous sounds all through the day (even in nights sometimes) during the ...
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0answers
16 views

Are there any individual animals that can thrive in a wide range of core temperatures? [closed]

Surely, some cold blooded animals are in a position where they can't escape the changing temperatures the environment throws at them, so natural selection would have enabled them to thrive in a wide ...
12
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1answer
100 views

What made this black cluster on a leaf?

I found this black slug-shaped thing on a leaf by my pond in western Sweden. It's about 15 mm long, positioned on a vertical leaf (I bent it to take the picture). And I don't even know where to ...
0
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1answer
100 views

Humans genetic/phylogenetic “next relative” in central Europe? [closed]

What species in central Europe in the phylogenetic tree shows the closest difference in time to the most recent common ancestor with Homo sapiens?
14
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3answers
2k views

Why are turtles classified as reptiles and not amphibians?

I understand that turtles are reptiles because like all reptiles, they have scales on their body. But turtles (specifically sea turtles) live on both land and water, very much like amphibians. Also, ...
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0answers
32 views

Why don't animals need filtered water? [duplicate]

Almost 10 years back when I was a kid, we had a picture in our school text of wild buffaloes drinking water from a river - which was visibly muddy. I asked my mother of why we need to drink filtered ...
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0answers
59 views

Why do horses recycle their endometrial lining while humans don't?

How does not recycling the endometrial lining of the uterus benefit humans (and other organisms that menstruate), while recycling it is beneficial to horses (and other organisms that undergo estrus ...
3
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2answers
89 views

Can animals also get Down syndrome?

I heard that animals cannot get Down syndrome or trisomy. Is that true and why can't they get it? They also have chromosomes.
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0answers
10 views

How much to larvae eat? (1. general and 2. specifically larvae of the bread beetle stegobium paniceum)

I'm no biologist or anything and thus the question might seem odd, but I couldn't find an answer anywhere on the web. I'm looking for information about how much larvae eat. To be exact I need to ...
2
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1answer
43 views

If crocodiles are k-selected, why do they supposedly “not age,” as in avoid senescence?

I recently saw a few sources stating that Crocodiles do not biologically age, implying negligible senescence. Basically, a 70 year old crocodile is in the same physical/health condition as a 7 year ...
1
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1answer
24 views

Which animal that lives in the forest makes this noise?

Which animal makes this noise? Link to audio file The file was recorded next to a forest in Germany.
8
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2answers
746 views

Are all quadrupeds edible? [closed]

I wonder if all quadrupeds (or, mammals, at least), are edible? From what I have collected, even down to fish, everything is edible apart from being sick or infected, and, apart from some glands ...
6
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2answers
104 views

Why would a mother reject her offspring if it has been “interfered” with by humans?

There was a recent incident at Yellowstone National Park in which tourists placed a bison calf in their vehicle, and that eventually led to the calf being euthanized. The National Park Service issued ...
4
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1answer
136 views

What were the camels' humps good for back in the polar areas?

I've heard that camels lived in the North America formerly and just in the last few thousands years they've migrated to the hot deserts. Thus they allegedly utilized the adaptations against the cold ...
0
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2answers
83 views

What is this animal? [duplicate]

Can someone tell me what is the name of this one? Then I can check a little more about it.
2
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1answer
34 views

How do mosquitoes orientate in the darkness?

An annoying mosquito (Culicidae) which kept me awake nearly the whole night lead me to this question. I have heard that mosquitoes can smell CO2 which could help them to orientate in the darkness, ...
19
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1answer
4k views

What is this crawling next to my house?

I just found this outside my house while walking the dog. I was thinking it's some kind of slug? It's been raining a lot lately and today, so maybe that has something to do with it being on the ...
4
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0answers
19 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, ...
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0answers
19 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 ...
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0answers
13 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 ...
2
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0answers
27 views

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

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
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1answer
19 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 reptile,...
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0answers
16 views

Do all parasitic worms lack tango receptors on their skin?

I read that the parasitic nematodes lack tango receptors on the surface of their body. Is this true for all the parasitic worms?
0
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2answers
35 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) ...
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0answers
23 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 ...
2
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0answers
39 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 ...
6
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2answers
119 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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1answer
69 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 ...
7
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1answer
124 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 ...
29
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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 ...
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?
3
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1answer
106 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, ...
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1answer
43 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 ...
1
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1answer
34 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 ...
4
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1answer
94 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 ...
34
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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
106 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?
1
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1answer
58 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 ...
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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?
5
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1answer
41 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 ...
11
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2answers
118 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
21 views

Would a python die if it ate a cane toad [closed]

I was thinking about the Burmese pythons that are invading the everglades and cane toads that were introduced in Australia.