You're in a minefield: Phrase your question
more carefully in the future.
Although this question is can be a legitimate scientific inquiry into
the genesis of a peculiar trait of a particular creature, one must always
be wary when the word "evolution" appears as the topic of a discussion.
Questions like the title of this node are often disingenuous attempts
to discredit natural selection, a theory which has been the target of
certain groups who claim it attacks their "faith". They misapply the label
"evolution" to it, which can mean a whole host of other things. Sadly,
or perhaps amusingly, whenever such people try to "disprove" natural selection
and thus "prove" the object of their "faith", they only demonstrate the
weakness of that faith.
Most perplexingly, they do this even though natural selection does not
rise or fall on the accuracy or inaccuracy of any religious beliefs. This
unreason often leaves reasoning people nonplused: How do you answer madness?
I am not going to attempt to characterize which category the first
writeup falls into; I sincerely hope it's the former.
However, the writeup contains some misstatements, as well as flaws in
the writer's reasoning. I am far from being a marine biologist,
but I think I can point the flaws out and offer some explanations of how
the sea mouse got its spines that are at least plausible.
We have been pointed to a news story that describes unusual characteristics
of spines of the "sea mouse" Aphrodita an invertebrate that feeds
on the bottom of the ocean. That is, when light strikes the spines
from one angle, they appear one color; from another angle, they appear
another color. The article is really about the possible applications
of the spines' properties to photonics.
We are led to believe that the sea mouse lives in the deep (Benthic)
ocean, where there is no light to be had. The creatures do appear
at depths of 2000 meters, however, species of aphrodita occur, according
to www.brittanica.com, starting just below the intertidal zone (10 meters
or greater), where things may be dim, but certainly not dark.
We are led to believe that the sea mouse emits light. I can find
no source that says that the sea mouse is bioluminescent.
Indeed, the cited article talks about the refractive properties
of the spines.
We are led to believe that emitting light or having distinctive coloration
serves only to attract predators. Nature is full of examples where
these are used:
as a means of communication
as a warning to predators of a creature's toxicity
as bait to the creature's prey
as a decoy, offering less vital parts of a creature for predators to eat.
I have no idea, of course, whether any of these apply to the sea mouse.
Suffice it to say, though, that these other creatures stand out and aren't
extinct. In fact, bioluminescence appears to be the rule in the deep sea,
rather than the exception.
When we are asked, "what benefits could accrue from emitting a dim
light in one of the darkest places on earth, other than to attract predators?",
we must answer back, "why would emitting a dim light attract more predators
than emitting a bright light?"
We are led to believe that the optical properties of the spines have
to be a selection advantage. They may, and then again they may not.
The spines' iridescence comes from their peculiar structure, hexagonal
columns of protein secreted by cells on the worm's body. It is possible
that this structural property of the spines is the primary benefit to the
creature, and any iridescence is just a side effect.
Finally, we are led to believe that the spines' optical properties
have to be perfect in order to be useful. If we are talking
about the structural advantage discussed in the last point, this requirement
for immediate perfection falls flat on its face.
However, let's really stretch, assume that that point is inoperative,
and that the spines' optical properties have some use. Let's assume
we need a traditional "gradualistic" explanation.
We cannot assume that the creature originated in the deep ocean and
has remained there since. If the creature originated in the intertidal
zone, where there is some light, an "intermediate form" (a lesser amount
of iridescence from the same amount of light) might have a beneficial effect
in a zone where there is more light. As the creature spread into
the deeper ocean, where there is less and less light, later generations
would be selected for more and more efficiency of refraction.
Enough of this, I think you get my point: It is entirely possible
for the sea mouse to have arisen via natural selection.