Tag Archives: Anatomy

Say what?

Elephants use their feet to detect and interpret vibrations in the ground.

The feet stomping display of aggression can be detected some distance away as warning vibrations traveling through the ground, causing the elephants to gather in defensive formations .

It has also been noted that if unknowns vibrations are detected, the animals vacate the area.

 

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(#79 of 100)

Gone Fishing

Fishing spiders (genus Dolomedes) do not spin webs to catch pray. Instead they hunt by anchoring themselves to shore with their hind legs and extending their front legs onto the water surface to detect movement much like other spiders use webs. When they detect the ripples from prey, they run across the surface to subdue it using their foremost legs, which are tipped with small claws.

They are able to travel on water because they are covered all over in short, velvety hairs which are unwettable (hydrophobic).

They are also more than capable of going underwater. The hairs on the abdomen trap air, allowing it to carry its own air supply when it submerges.

The nursery web spider (Dolomedes minor) do not restrict themselves to stay close to open water but are capable fisherman none the less.

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New Zealand Nursery Web spider (Dolomeded minor)

(#54 of 100)

Eyes too big for my stomach? Not a problem.

When the sea star encounters food too large for its mouth it can pass part of its cardiac stomach through its mouth to envelop and digest the meal outside its own body.

It also uses this trick when eating shellfish. It pries the shell slightly open and inserts its stomach through the crack to digest the shellfish inside its shell.

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Sea star at Wellington’s south coast.

(#39 of 100)

Myth became Legend, Legend became Truth.

Why do the Afrikaans speaking people refer to a grey rhinoceros as white? The popular etymological story goes like this:

The Dutch at the Cape of Good Hope called the white rhinoceros the “wide” (Dutch: wijd, Afrikaans: wyd) rhinoceros to refer to its wide mouth adapted for grazing – a grass eater. Its mouth is an anatomical feature that distinguishes it from the black rhinoceros, which is a browser – a leaf eater.

The English misheard/mistranslated ‘wijd’ and started calling the rhino “white”.

Some years later, the Dutch/Afrikaners  on hearing that the English refer to this rhino as white, decided to use the Afrikaans translation for white rather than stick with the anatomically correct name they purportedly gave it earlier.

You won’t be alone in your incredulity; Kees Rookmaaker, Chief Editor of the Rhino Resource Center wrote in a 2003 publication “the popular explanation that ‘white’ is derived from the Afrikaans word ‘wyd’ is examined and found to be unsubstantiated and historically incorrect.”

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White rhinoceros (Ceratotherium simum) at Pilanesberg.

(#37 of 100)

Some cats purr others can only roar.

Some cats species can purr and others roar but none do both.

It was thought that the characteristics of the hyoid bone determine which cats can roar as all the roaring cats:

  • lion (Panthera leo)
  • jaguar (Panthera onca)
  • tiger (Panthera tigris); and
  • leopard (Panthera pardus)

share the same hyoid bone structure.

However, turns out the snow-leopard (Panthera uncia) also shares the same hyoid bone structure, but does not roar but purr.

Back to the drawing board I guess.

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Panthera leo the roaring cat with the biggest roar.

(#36 of 100)

 

I have a very complex heart.

Crocodiles have a heart with four chambers (two connected to the lungs and two connected to the rest of the body) just like birds and mammals.

However crocodiles also have the ability to have their heart act as a three chambered heart to mix oxygenated and deoxygenated blood (through the foramen of Panizza) to slow down their metabolism.

The also have a further mechanism (a cog toothed valve) to completely block the flow of blood to the lungs when submerged.

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Nile Crocodile, (Crocodylus niloticus)

(#22 of 100)

One mighty set of teeth.

Did you know, during their lifetime, elephants have six successive sets of molars? A new set develops in the back of the jaw and moves forward to replace an older set that has worn away grinding down the vegetation they eat.

A single tooth can weigh as much as 5 kilograms.

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African elephant (Loxodonta africana) foraging in the Addo Elephant National Park.

(#13 of 100)