Shroomerz420's Aquatic Friends

Mar 4, 2011
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Shroomerz420's Aquatic Friends (56K Warning)

I decided to make this thread as a place to share my photos. Let me know what you think! *twirlysmi



I never realized Ottos had hair until I took this picture.


"I always feel like...somebody's watching me"













 

Last edited:
Mar 4, 2011
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all very nice pics!
the otos' hairs are likely tiny spines jutting out from the skeleton/skin.
Thank you! :)

Yeah after a little searching...I found this. I was freaking out for a little bit thinking my Ottos had a disease or something. Whew!
http://www.otocinclus.com/anatomy.html

Apparently they are called odontodes and they are actually made from bone material. Pretty crazy stuff.
 

Mar 26, 2011
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Malden, MA
#8
Huh...I wonder if the odontodes work the same way that shark skin works to direct water molecules around the shark for optimum hydrodynamics. They are quick little suckers (pun!) when they want to be and maybe that would help them use less caloric energy to hang onto rocks and plants in a strong current, since they are river fish.

Found this online:
"The denticle crowns of the White Shark are highly sculptured, each with three longitudinal ridges that terminate in a rearward-pointing cusp. Although it may seem counter-intuitive for an aquatic animal to be anything but smooth as possible, there are actually sound hydrodynamic benefits to be gained from such sandpaper roughness. How strategic roughness can yield aero- and hydro-dynamic benefits has elicited a great deal of research in recent years. Consider the humble golf ball. Those characteristic dimples are not created equal: the indentations around the equator of the ball are actually slightly deeper than those at the poles. This deceptively simple design feature grants a golf ball in flight and with the proper backspin an additional two seconds of 'hang-time' — increasing driving range by as much as 80 feet (24 metres) — and reduces the incidence of hooks and slices by as much as 75%. Similarly, in fighter jets or fast ships, the secret to their phenomenal speed lies in fine, V-shaped grooves. These grooves must be very closely spaced — about as close together as the grooves on an old-fashioned phonograph record (Anyone remember those?). Such closely-spaced grooves appear to reduce drag by preventing eddies from coming in contact with the surface of a moving body. Nowadays, there is hardly an American military aircraft or vessel that does not somehow benefit from the fluid dynamic efficiency of incorporating strategically-placed, V-shaped grooves along the fuselage, hull, and foils. But, whenever there is a physical principle that provides an elegant solution to a practical environmental challenge, it seems that Nature always beats us to the punch. Collectively, the tiny, three-ridged dermal denticles of the White Shark create closely-spaced grooves similar to those on high-speed air or water craft. These denticles very probably impart similar drag-reducing properties to the shark. Thus, without understanding the first thing about golf balls or military craft, the White Shark has been employing many of the same fluid dynamics principles for millions of years.
In a short but fascinating 1982 paper, Wolf-Ernst Reif and his co-worker A. Dinkelacker reviewed the hydrodynamics of dermal denticles in fast-swimming sharks. Reif and Dinkelacker found that the crowns of dermal denticles in the Shortfin Mako and other fast-swimming sharks are smooth and almost ridgeless on the tip of the snout and leading (anterior) edges of the fins, but elsewhere on the body the crown ridges are quite steep, with depths one-half to two-thirds their width. They also found that the alignment of these crown ridges varies over the body, closely approximating path-of-least-resistance flow of water over the surface of the shark. The smoothness of denticles on the leading edges of the snout and fins offer the least resistance to these areas of minimal boundary layer thickness. In contrast, the alignment of crown ridges with the 'natural' flow-direction of water over the shark's body can be expected to maximize drag reduction by reducing turbulence, thereby preventing eddy formation. The arrangement of dermal denticles in the White Shark is probably very similar to that exhibited by the Shortfin Mako. Thus, like a dimpled golf ball, a grooved Great White may glide farther on a given amount of energy than would a smooth one.
In a 1986 paper, biologists William Raschi and Jennifer Elsom reviewed the drag-reduction properties of shark dermal denticles. Raschi and Elsom examined the denticles of 15 species of shark and found that those of fast-swimming pelagic species — such as the Shortfin Mako — are consistently smaller and lighter than those of sluggish or bottom-dwelling species. Therefore, the relatively small, light-weight dermal denticles of the White Shark are probably adapted for fast swimming more than armor-like protection — yet another compromise between form and function. In addition, they found that the Shortfin Mako and other fast-swimming species consistently had ridge characteristics nearer those values predicted as optimal for burst speeds. Raschi and Elsom also found that, despite growth-associated increases in the crown size of denticles, the height and spacing of the scales' longitudinal ridges remained nearly constant in all species examined. This suggests that some important functional feature may be maintained throughout a shark's life. That feature is very probably drag reduction — in a 1984 report, Raschi and ichthyologist Jack Musick discovered that the longitudinal ridge system created by shark dermal denticles is responsible for drag reductions as great as 8%. That percentage represents a substantial energy savings, and it seems unlikely that the White Shark would not take advantage of the benefits afforded by this mechanism.
There is at least one further benefit of sharks' hydrodynamically sculpted dermal denticles: stealth. Despite pioneer undersea explorer Jacques-Yves Cousteau's poetic description of the marine environment as a "silent world", the ocean is full of noise. Mournful songs of lonely whales, exuberant squeals and clicks of cavorting dolphins, multitudinous croaks and yaps of reproductively-ripe fishes, and the incessant, static-like chorus of snapping shrimps vie with the mechanical rumble of ocean-going ships and the frenetic buzz of speedboats. If you were to lower a hydrophone (underwater microphone) near a school of teleost fishes, you would quite easily hear the sloshing sounds of water turbulence, created by their swimming movements. The large, overlapping scales of teleosts are not nearly as hydrodynamically 'clean' as the dermal denticles of sharks. If you were to place the same hydrophone near a cruising shark, no such swimming sounds would be heard. Sharks are, literally, "silent hunters". For the Great White, this hydrodynamic side-effect probably confers tremendous advantages when stalking prey: the hapless fish or sea lion almost never hears the shark that caught it."