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Dolphin
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| [Note Guidelines] Photographer's Note [Dutch] |
Today another picture from Harderwijk but this time from a dolphin.
There are 4 little dolphins born this year.
I hope you like it.
Thanks for critique on my previous post.
Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacean order, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are among the most intelligent animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.
The name is originally from Ancient Greek δελφίς (delphís; "dolphin"), which was related to the Greek δελφύς (delphys; "womb"). The animal's name can therefore be interpreted as meaning "a 'fish' with a womb".
The name was transmitted via the Latin delphinus, Middle Latin dolfinus and the Old French daulphin, which reintroduced the ph into the word.
The word is used in a few different ways. It can mean:
Any member of the family Delphinidae (oceanic dolphins),
Any member of the families Delphinidae and Platanistoidea (oceanic and river dolphins),
Any member of the suborder Odontoceti (toothed whales; these include the above families and some others),
Used casually as a synonym for Bottlenose Dolphin, the most common and familiar species of dolphin.
This article uses the second definition and does not describe Porpoises (suborder Odontoceti, family Phocoenidae). Orcas and some closely related species belong to the Delphinidae family and therefore qualify as dolphins, even though they are called whales in common language. A group of dolphins is called a "school" or a "pod". Male dolphins are called "bulls", females "cows" and young dolphins are called "calves".
In 1933, three strange dolphins beached off the Irish coast; they appeared to be hybrids between Risso's Dolphin and the Bottlenose Dolphin. This mating was later repeated in captivity producing a hybrid calf. In captivity, a Bottlenose Dolphin and a Rough-toothed Dolphin produced hybrid offspring. A Common-Bottlenose hybrid lives at SeaWorld California. Other dolphin hybrids live in captivity around the world or have been reported in the wild, such as a Bottlenose-Atlantic Spotted hybrid. The best known hybrid is the Wolphin, a False Killer Whale-Bottlenose Dolphin hybrid. The Wolphin is a fertile hybrid.Two Wolphins currently live at the Sea Life Park in Hawaii; the first was born in 1985 from a male False Killer Whale and a female Bottlenose. Wolphins have also been observed in the wild.
Dolphins, along with whales and porpoises, are descendants of terrestrial mammals, most likely of the Artiodactyl order. The ancestors of the modern day dolphins entered the water roughly fifty million years ago, in the Eocene epoch.
Modern dolphin skeletons have two small, rod-shaped pelvic bones thought to be vestigial hind limbs. In October 2006 an unusual Bottlenose Dolphin was captured in Japan; it had small fins on each side of its genital slit which scientists believe to be a more pronounced development of these vestigial hind limbs.[8]
Anatomy
Dolphins have a streamlined fusiform body, adapted for fast swimming. The tail fin, called the fluke, is used for propulsion, while the pectoral fins together with the entire tail section provide directional control. The dorsal fin, in those species that have one, provides stability while swimming.
Though it varies per species, basic coloration patterns are shades of grey usually with a lighter underside, often with lines and patches of different hue and contrast.
The head contains the melon, a round organ used for echolocation. In many species, elongated jaws form a distinct beak; species such as the Bottlenose have a curved mouth which looks like a fixed smile. Some species have up to 250 teeth. Dolphins breathe through a blowhole on top of their head. The trachea is anterior to the brain. The dolphin brain is large and highly complex and is different in structure from that of most land mammals.
Unlike most mammals, dolphins do not have hair, except for a few hairs around the tip of their rostrum which they lose shortly before or after birth. The only exception to this is the Boto river dolphin, which has persistent small hairs on the rostrum.
Dolphin’s reproductive organs are located on the underside of the body. Males have two slits, one concealing the penis and one further behind for the anus. The female has one genital slit, housing the vagina and the anus. A mammary slit is positioned on either side of the female's genital slit.
Senses
Most dolphins have acute eyesight, both in and out of the water, and they can hear frequencies ten times or more above the upper limit of adult human hearing. Though they have a small ear opening on each side of their head, it is believed that hearing underwater is also if not exclusively done with the lower jaw, which conducts sound to the middle ear via a fat-filled cavity in the lower jaw bone. Hearing is also used for echolocation, which all dolphins have. It is believed that dolphin teeth function as an antenna to receive incoming sound and to pinpoint the exact location of an object. The dolphin's sense of touch is also well-developed, with free nerve endings densely packed in the skin, especially around the snout, pectoral fins and genital area. However, dolphins lack an olfactory nerve and lobes and thus are believed to have no sense of smell. They do have a sense of taste and show preferences for certain kinds of fish. Since dolphins spend most of their time below the surface, tasting the water could function like smelling, in that substances in the water can signal the presence of objects that are not in the dolphin’s mouth.
Though most dolphins do not have hair, they do have hair follicles that may perform some sensory function. The small hairs on the rostrum of the Boto river dolphin are believed to function as a tactile sense possibly to compensate for the Boto's poor eyesight. |
siggi, boreocypriensis, goldyrs, zulfu, parasbhalla, Noisette, jaycee, tcr, CeltickRanger has marked this note useful
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- rkyobo
![Silver Star Critiquer/Silver Note Writer [C: 29 W: 5 N: 21]](http://i1.treknature.com/misc/s-n-s.gif)
(213) - [2009-10-02 23:30]
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Great shot of the dolphin - very good detail!
- siggi
![Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1380 W: 56 N: 4759]](http://i1.treknature.com/misc/g-g-g.gif)
(16364) - [2009-10-03 0:00]
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Hello Gert
Lovely capture.Lighting,POV,colors,clear details,framing and composition are wonderful.
TFS.Best regards Siggi
Hi, Gert,
Wonderful shot! Very positive photo, well done!
My compliments!
Serghei
Hi and Good Morning big Bro,
Lovely capture of a delphin from nice POV.
TFS and have a nice saturday!
Cheers,
Bayram
great portraite, great focus and POV. compsition and colors superb, Gert.
have a nice weekend
Ahmet
Hi Gert,
Superb portrait of this amazing dolphin, excellent sharp and details! Very well done.
TFS. Cheers. Ferran.
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- zetu
![Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 652 W: 15 N: 1622]](http://i1.treknature.com/misc/g-s-g.gif)
(6301) - [2009-10-03 2:40]
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Hello Gert
Nice portrait taken with beautiful colors and great details
Regards
Razvan
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- rommel
![Gold Star Critiquer/Silver Note Writer [C: 93 W: 0 N: 49]](http://i1.treknature.com/misc/g-n-s.gif)
(869) - [2009-10-03 4:36]
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Hi Gert,
Interesting notes.Great capture of this dolphin,with its friendly smile and small eye.Good POV and nice detail showing the teeth , body markings and droplets of water.
erwin...
WHat an amazing shot of this most intelligent of beings!
Bravo!
Goldy
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- zulfu
![Gold Star Critiquer/Gold Note Writer [C: 1065 W: 0 N: 162]](http://i1.treknature.com/misc/g-n-g.gif)
(870) - [2009-10-03 11:51]
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Hello Gert, lovely and great shot of a cute dolphin.
TFS and R's,
Mehmet
Hi Gert,
Lovely closeup shot of an adorable dolphin with great details! I like the sharpness and POV in the shot. The colors are perfectly natural. Great composition!
best regards,
Paras
Hello Gert
wonderful portrait of this Dolphin, very fine details on the main subject and the water
superb composed shot with great lighting and colors
Have a good night
Jacqueline
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- jaycee
(21912)
- [2009-10-05 16:46]
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Hi Gert,
I was away for a few days and missed some of your shots. I had to choose this dolphin for today's comment. Wonderful timing to capture his smiling face. The colors and clarity are marvelous. I love the water with the droplets and the waves he is making. I can't believe how clear the little teeth are! This is priceless.
Jane
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- tcr
(934)
- [2009-10-05 17:06]
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Hello Gert.
A pleasant image of this smiling dolphin.
Very well taken.
Greetings and TFS.
hello Gert
a very beautiful photo of this wonderful animal that is the Dolphin,
fine POV, DOF and framing, fine focus great sharpness
and details, and wonderful glance of the Dolphin, TFS
Asbed
