How About 15 Primary Colors!
Sir Frederick
ScienceWeek http://scienceweek.com
The following points are made by Thomas W. Cronin (Current
Biology 2006 16:R235):
1) Stomatopod crustaceans are commonly known as mantis shrimp,
because their prey-catching (raptorial) appendages resemble those
of praying mantises. They are strictly marine and are quite
distinctive from all other crustaceans, having separated from
them roughly 400 million years ago and having evolved on their
own unique track ever since. About 500 species are recognized
today, most living in shallow tropical waters on sand flats or in
coral reefs. While unfamiliar to most people, mantis shrimps are
actually very common in these habitats.
2) Stomatopods are destructive creatures. They actively hunt down
and attack prey, using their mantis-like arms either as spears to
snatch small invertebrates and fish from the water, or as clubs
to bludgeon snails and small crustaceans to death. Because they
tend to wipe out the animals in small seawater aquaria within
hours of their arrival, they are widely hated by aquarium
hobbyists, who unwittingly import them in coral rock placed in
the tank.
3) Most stomatopods are small, typically a few centimeters long,
but some get to be the size of a lobster and can actually smash
through the glass wall of an aquarium. Despite their pugilistic
nature, mantis shrimps are quite attractive animals, colorfully
marked and interesting to watch as they wander about, probing
into cracks and crevices for potential food. Their compound eyes
extend anteriorly on stalks, and the eyes are constantly in
motion, giving mantis shrimps an air of inquisitiveness and
intelligence. Being so unusual, mantis shrimps have been called
"shrimps from Mars", but they have also been likened to
crustacean primates because of their behavior and their alert,
active eyes.
4) Stomatopods can distinguish colors. Mantis shrimps have the
greatest diversity of color receptor types known for any animal.
Many species have ten different photoreceptor spectral classes
that see in the human "visible" spectrum (400 to 700 nm) plus
another five or six types that operate in the ultraviolet. The
color receptors differ in the visual pigments they contain, and
some are spectrally tuned by colored filter pigments that overly
each actual receptor. Mantis shrimps have been trained to select
an object of a particular color from an array of objects of
different colors, demonstrating that they have true color vision
and can therefore make discriminations based upon hue alone and
not brightness. The receptors that mediate color vision are
aligned in a linear arrangement in the compound eye and thus
sample only a thin strip of visual space. The rest of the visual
field is apparently seen only in shades of brightness, so to fill
in the missing color, the eyes must scan over objects of
interest. To give a sense of the complexity of mantis shrimp
color vision, humans have only four classes of photoreceptors,
compared to the 15 or so of mantis shrimps, and only three of
those are cone types used for color vision (the other is the
rods, used in dim light).[1-4]
References:
1. R.L. Caldwell and H. Dingle, Stomatopods. Sci. Am. 234 (1976),
pp. 80 89
2. T.W. Cronin and J. Marshall, The unique visual world of mantis
shrimps. In: F. Prete, Editor, Complex Worlds From Simple Nervous
Systems, MIT Press, Cambridge MA (2004), pp. 239 268
3. http://www.ucmp.berkeley.edu/aquarius/
4. N.J. Marshall, J.P. Jones and T.W. Cronin, Behavioural
evidence for color vision in stomatopod crustaceans, J. Comp.
Physiol. A 179 (1996), pp. 473 481
Current Biology http://www.current-biology.com
ScienceWeek http://scienceweek.com
Don H
news:v0m442lnelctvscdb...@4ax.com...
yellow, orange, red - and various mixtures of these, hues, or intensities.
Are these all primary? or are only red, yellow, blue - as the others
(secondary) can be derived from them?
Does non-human Nature have colours, or are colours
psychological-physiological re species concerned.
Mantis shrimps have a greater refining capacity than ourselves, it seems,
so as to distinguish between finer degrees of light wavelength.
Brian Fletcher
"Don H" <donlhu...@bigpond.com> wrote in message
news:hRB0g.8230$vy1....@news-server.bigpond.net.au...
> "Sir Frederick" <mmcn...@fuzzysys.com> wrote in message
> news:v0m442lnelctvscdb...@4ax.com...
>> EVOLUTIONARY BIOLOGY: ON STOMATOPODS
>> ScienceWeek http://scienceweek.com
>>
> yellow, orange, red - and various mixtures of these, hues, or intensities.
> Are these all primary? or are only red, yellow, blue - as the others
> (secondary) can be derived from them?
> Does non-human Nature have colours, or are colours
> psychological-physiological re species concerned.
> Mantis shrimps have a greater refining capacity than ourselves, it seems,
> so as to distinguish between finer degrees of light wavelength.
>
>
I would suggest seven, as there are seven notes in the octave. This ties in
with ancient teachings of "light and sound" being the essence of our psycho
sematic structure. Surat Shabda yoga , Sant Mat and more recently Eckankar
being examples.
Biblically "let those who have eyes to see and ears to hear" , and
scientifically, the source of vibration, and holographic capacity of light.
BOfL
Publius
> To give a sense of the complexity of mantis shrimp
> color vision, humans have only four classes of photoreceptors,
> compared to the 15 or so of mantis shrimps, and only three of
> those are cone types used for color vision (the other is the
> rods, used in dim light).[1-4]
Interesting post, Sir Fred. Birds have 5 color opsins, so their color vision
is also more subtle than ours. Most mammals have only two; primates and some
rodents have 3.