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There are very few things in the world that aren't beneficial to some lifeform. Even if you were to, say, spill a mixture of persistent broad-spectrum poisons on an area that killed off 99.9% of all species there, the remaining 0.1% that did survive would benefit from the lack of competition. The "great garbage patch" is hardly so extreme a phenomenon, but ...

In the case of whales, I always thought that it was something to do with the fact that they rely upon buoyancy to support their weight and this seems to support that view: When whales, including small whales or dolphins become stranded on beaches they suffer from the pressure of their own weight on their organs,in the water they are weightless. They ...

The link you give doesn't mention limbs sticking out of the body wall, but only vestigial hind limb elements. Many whales do retain pelves and femora, as this page at the Bergen Museum shows. Given the variation in limb development across vertebrates, it would not be surprising to find more distal elements (but I would be very surprised if they extended past ...

Here there are spectrograms from Bottlenose dolphins (Tursiops truncatus), Killer whales (Orcinus orca) and False killer whales (Pseudorca crassidens). Here there are spectrograms for Humpback whale (Megaptera novaeangliae) and from Sperm whales (Physeter catodon or Physeter marcocephalus) Here there are spectrograms from Blue whale, Fin whale and Minke ...

Dolphins can hear above 110 kHz, and produce vocalizations in this range. Clicking has evolved in proposes and sperm whales and is predominantly above 100 kHz (to avoid being heard by killer whales). It's a bit subjective, of course: if you do a frequency decomposition of a click, it will always have some component with very high frequency. That dolphins ...

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 ...

The mechanisms of osmoregulation is different for sharks (and other elasmobranch fishes) and teleost fishes. In Elasmobranchs the body osmolarity is maintained equal to the seawater by Na⁺ Cl⁻ and urea. Toxicity because of high concentrations of urea (strong chaotrope) is counteracted by high levels of trimethylamine oxide (TMAO). So, the elasmobranchs do ...

I'm not sure that all phytoplankton perform the same type of photosynthesis. Originally, people thought that they all performed C4, on the basis of genome sequencing, which revealed the presence of genes important for C4 photosynthesis. However, experiments on individual species seemed to indicate that the phytoplankton were performing multiple types of ...

My first question would be is there any external indication of them such as air holes or anything else that you can assess from the surface? I would think that if there is, you could use transects and a quadrat. If you need to dive for them you can obviously make a weighted quadrat by filling pvc pipe with sand and gluing it together. Then take an area ...

How about marine reptiles? Sea snakes have a paddle-like tail, so perhaps you would claim that as a fin, but maybe marine iguanas would qualify? And, of course, sea turtles.

It is more efficient to use fins than feet, hooves, or other similar body parts. It is the same reason that you can swim faster while wearing flippers. Having a larger surface area allows animals to push against more water, so that they have more force when swimming. Here is a picture of the bones in a dolphin fin. They are extremely similar to the bones in ...

This is the one I've heard of - Its a sealed acrylic globe that contains algae and brine shrimp. There are quite a few references in the bibliography here to previous systems. Of course, it needs sunlight, but all the elements are recycled. Its really closed and has reasonable endurance. The basic commercial version of his closed world -- sold under ...

This post is pretty well written and seems to say that the evolutionary forces that produce shell color like this is not known. There are suggestions that the color is camoflage or the result of metabolic byproducts or that the pigments serve to strengthen the shell. Its hard to believe some of these theories given that some shells do fine without coloring ...