This week I am talking about an artistic fish that
creates elaborate, and time consuming, pieces of artwork to impress and attract
females. This artwork was discovered by divers in 1995 and it wasn’t until 2011
that scientists were able to say who or what created them. It was a small male
puffer fish Torquigener sp.
Many marine animals are known to create nest sites
on the seafloor however; the puffer fish creates unique characteristics not
found anywhere else in the ocean. Radially aligned peaks and valleys that are
created outside the actual nest site; the peaks are decorated with shells; and
the sand is altered to create irregular patterns in the nest site itself. These
patterns were created before mating and after a female has visited the site,
they collapse. Females were found to evaluate the artwork and make their mate
choice based on the nest construction, although what exactly they look for in a
nest site is still unknown.
The specific patterns created provide more than just
an aesthetic function. The radially aligned peaks that the fish constructs aids
in providing lots of soft sand that can be deposited in the nest site. The males flap their fins in order to dig up
the sand and create the valleys and peaks. Also, due to fluid dynamics, and the
construction of the outer nest, the sand that the fish stirs up will be
propelled towards the centre of the nest and not outside it so the males efforts
are not done in vain.
References
Kawase H, Okata Y & Ito K.
(2013). Role of huge geometric circular structures in the reproduction of a
marine pufferfish. Scientific
reports, 3.
That is a truly phenomenal example! I think I’m going to have to use it in my lectures on sexual selection! I wonder – did the researchers give any indication as to who they can create such a perfect circular structure? Are other patterns created? This was a lovely post!
ReplyDeleteThis was a really interesting post! Do you know if females continually choose different mates or if they stay with the same male for the duration of their life?
ReplyDeleteHey Courtney. They didn't mention if they mate for life however, they did notice that once the male has been successful and looked after the eggs, the nest slowly is destroyed because the male no longer maintains it. He then goes to find a new area to begin constructing another nest so I assume that they have multiple partners.
DeleteHey Tasmin. They don't say how they are able to make it, at least appear to be , perfectly circular but they did observe different behaviours of the fish during construction. It generally takes between 7-9 days to create the pattern and there are different phases. They start off with making a general circular shape and then start to make the valleys and peaks. Once these are done they then go back over the construction and start refining it to make it smoother and more aesthetically appealing. How they are able to make it so geometrically correct is amazing and could be the basis for further study.
ReplyDelete