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Short answer Under ideal conditions, an octopus may survive several minutes on land. Background Octopuses have gills and hence are dependent on water for the exchange of oxygen and carbon dioxide. Gills collapse on land because of the lack of buoyancy (source: UC Santa Barbara). Octopuses have three hearts. Two of these are dedicated to move blood to the ...


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There are a couple of advantages and disadvantages of possessing the eyes of octopuses. The first advantage of the octopus eye is that it has no blind spot. This means that octopuses can see everything that is going on in their environment, and are more aware of predators and prey than some vertebrates. Also, they have many more photoreceptors than ...


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Some moth actually do use clicks for their own echolocation: "Noctuid moths (Noctuidae) are the only group of invertebrates for whom echolocation was demonstrated": Lapshin & Vorontsov 1998 Lapshin et al 1994.


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It's hard to identify from the photos provided, but I think it is Chloeia flava (a species of polycaete worm, within the phylum Annelida), also known in English as the "Golden Fireworm". The size is roughly similar to what you describe (they are typically about 7-10 cm long). The individual you observed looks like it lives in sandy bottom environments (not a ...


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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 ...


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Asterosaponins are the class of compounds - they have a cholesterol like organic core. Apparently, these saponins make pore-forming complexes with Δ5-sterols of cell membranes, and so are deadly to all usual kind of life, including bacteria and fungi. Quote: Starfish and sea cucumber cell membranes are resistant to their own saponines due to the ...


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It really depends on which type of gastropod you are talking about, since different types of snails, have different types of eyes. Marine gastropods could only become more mobile, when their abilities of sight had improved. This happened, when the eye cup deepened and the visual opening narrowed. An effect was the result, which in historical time was ...


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Breathing during digging And if all that wasn’t enough responsibility for these claws, they also are used for digging. While most digging crabs use their back legs to burrow backwards into the sand, the shame-faced crab uses the claws like little bulldozers, excavating the sand forward so the crab sinks downward until it is completely covered by the ...


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Why so many molluscs exhibit sinistral winding? The estimates of the number of molluscs vary quite greatly between 50,000 and 200,000 species. Of those molluscs species, about 70'000 are Gasteropoda. Gasteropa is most diverse Mollusca phylum. The winding you describe is present in all Gasteropoda and is often called the torsion. So the answer to why there ...


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I can't be certain, but it is probably the pupal shell of a crane fly (daddy longlegs, Tipula palidosa). Here is an image to compare, and you can find lots more with a Google image search. In the UK at least, these are colloquially referred to as leatherjackets and if you find one in soil before the adult has emerged it will often twitch.


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This is one of those speculative questions where you don't have a definite answer unless you specifically experiment and find out for yourself. It is a known fact that earthworms breathe through diffusion. It has a thin cuticle over its body and requires moist skin which is achieved by a slimy mucous (reference). It is interesting to note that earthworms ...


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As others have indicated, I also haven't seen direct evidence of echolocation in insects. However, there is much evidence that the auditory system of e.g. moths can hear ultrasound generated by bats (Waters, 2003). According to Waters (2003) moths mainly use this to avoid predation. The review also contain many useful references and examples of moth ...


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These are a kind of ramshorn snail, as Jestep correctly guessed. Now they are grown up and they are clearly identifiable as ramshorn. I will post photos of adults when I get the opportunity.


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Short answer Gills in terrestrial crabs serve a role in water storage and ion homeostasis. Background Crustaceans are a huge group of species within the phylum of arthropods, including crabs, lobsters, crayfish, shrimp, krill and barnacles. Because of the huge variety of species within the crustaceans, I'll focus this answer on terrestrial crabs. Air-...


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I have looked about the topic and I have asked experts and the best aproximation to know the vertebrate host from arthropod blood meals is targeting mitochondrial genes because you can get clean sequence data due the fact that only one allele is present rather than two. Within the mitochondrial genome, you should select a gene which has been widely ...


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Three factors that influence the number of legs are: 1) Sex : In some species of myriapoda, the females have been found to have more leg segments than males (reference) eg: Himantarium gabrielis 2) age Growth is by adding segments and legs with successive molts (anamorphic), and myriapods continue to add additional segments and legs after they ...


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Jellyfish move by a form of jet propulsion and it moves in the direction that the head is facing. If it needs to change direction, it just needs to pivot and propel itself in the direction that it needs to move. Comb jellies (which are not really jellyfish) have cilia that beat continuously in the water for it to move forward. So water currents are not ...


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As far as I can tell, the answer is no. It's hard to prove a negative so the best I can do is that none of the articles in the literature I've been able to comb through have any mention of invertebrates at all. What I can give you is that some moths use clicks to jam bat echolocation and some fish are sensitive to echolocation, "raising the possibility ...


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Caenorhabditis elegans is a nematode. Eisenia fetida is an annelid. They both are lophotrochozoans (more specifically, trochozoans). Time of Divergence According to Michael Lynch, there are about 41 amino-acid substitutions per site between Annelida and Nematoda. According to Lynch's data, I estimated that this difference is roughly equal 100 million ...



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