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1

Since asking this question, I've learned that 97% of male mammals do not have concept of "beauty" and will mate with every female indiscriminately. These species do not have any paternal investment, so the males are not picky. In other 3% of mammals (~100 species) and a lot of birds, there is a significant degree of paternal investment in offspring. Species ...


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The so called horizontal axis (rosto-caudal) is parallel to the body of the rat. Vertical is just vertical when the rat is in its normal standing position and medio-lateral is horizonral and perpendicular to the rat's body. The head is the origin.


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Wikipedia has a quite didactic article on this: https://en.wikipedia.org/wiki/Anatomical_terms_of_location#Axes These terms are complementary with a mathematical coordinate system: if you are describing a system of axis for a cylinder, you will need to specify that (e.g.) $z$ is along its symmetry axis, here you will say that $z$ is along the rostro-caudal ...


1

The moss froglet is an example of a frog which lays eggs on land and the tadpoles develop over several months in the egg mass amongst moss. The Moss Froglet is a most unusual frog in that tadpoles develop on land. Breeding occurs from November to February. Four to 16 large eggs are laid in clumps of sphagnum or lichen and the tadpoles develop within the ...


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b) Mature RBCs Reason : Mitochondria also have their own DNA and Nuclear DNA is already present in Nucleus . Since enucleated ovum lacks nucleus but has Mitochondria therefore it has DNA presence while Mature RBCs lack mitochodria (to cease cellular respiration of the rbcs) and nucleus (for movement across the thin wall of capillaries with ease ) . Thus ...


1

Yes, a red fox and a kit fox could produce hybrid offspring, but it would be sterile. Sterile red fox / arctic fox (V. lagopus) hybrids have been bred for the fur trade for decades (source). Arctic foxes are quite closely related to kit foxes, and both species are equally distantly related to red foxes, so since one can produce hybrids then the other ...


5

There are two answers if the question refers to genomic DNA (neither enucleated ova nor mature RBCs have genomic DNA). However, since the question doesn't specific genomic DNA, we can exclude enucleated ova, which would still have mitochondria and therefore mitochondrial genomic DNA. Mature RBCS (at least in most mammals) do not have mitochondria, so the ...


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This is not a marsupial such as an opossum, since no marsupials are native to the region. It looks to be a rodent of some kind, probably a species in the Muridae family. Which species is it is exactly is hard to tell, since there are many species in Muridae which look quite similar, but my best guess is that this is a Tamarisk jird. It could also ...


8

This is a white morph red fox, not an arctic fox. As noted in the question, this fox has larger, more pointy ears than an arctic fox, and the second picture shows it to have a longer muzzle as well. Another clue is that these pictures were taken in the springtime or early summer (which you can tell from the new growth on the plants in the picture), and ...


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Camel RBCs are anucleate [1, 2]. The dark structure seen in microscopic images is not nuclei but a network of microtubules called the marginal bands. Marginal bands cause these RBCs to adopt an ellipsoid shape. The unique shape of these RBCs possibly allows them to survive osmotic stress and is probably advantageous to a camel under extreme dehydration. ...


33

Short answer It is a flying lemur (there exist only 2 species). Flying lemurs and primates are together a sister clade to treeshrews. Easy source of information Have a look at onezoom.org or tolweb.org by yourself! onezoom.org is more recent and clearly more trustful. It has the default of showing only fractions of the whole tree of life though. Tree of ...


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The most closely related animals to primates are colugos (order Dermoptera). The next most closely related after colugos are tree shrews (order Scandentia). The next most closely related after tree shrews are rodents (order Rodentia) and lagomorphs (order Lagomorpha) (rabbits, hares, and pikas). Sources: Wikipedia's section on the evolutionary history ...


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Perhaps also Habitat. The term typically refers to the zone in which the organism lives and where it can find food, shelter, protection and mates for reproduction...


3

959 Somatic Cells according to WormBase and The WormBook.


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There is no reason to believe that total nerve "wiring" (or combined length) does not increase with the size of the animal, although the number of neurons in the brain (and the number of connections they make via dendrites) matters as well. Animals with long necks, legs and tails have long nerves. Ancient sauropods may have had the longest nerves (referring ...



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