richard@gryphon.COM (Richard Sexton) (10/25/89)
(This is cross posted to news.groups to illustrate the class
of article that is somewht inappropriate for rec.aquaria, of
no interest to readers of sci.bio, and to sci.misc to demonstrate
the silliness of posting to a top level misc group as somebody
suggested. This is just the kind of article that annoyed me
when I was a begining aquarist, because I was then more
interested in what color gravel to use, which is a very
good topic of dicsussion for rec.aquari*, but I feel that
Sci.aquaria is the only intelligent place to post this)
[As long as I have the readers of sci.bio on the stick here
does anybody have *ready and easy* acess to the zoological
record ? I need all the pointers to information I can
get on aquatic plants of the genus Aponogeton - specifically
A. nana and A. caprinii]
I recently talked to Andre Schonewille jr. in Holland about various
things and was going to post this to the killifish mailing list as
it's mostly about killies, but decided to post it here as well
as one part of this is of interest to anybody that breeds
fish. That part is noted by `******' if you want to skip
straight to that part.
I'm going from my roughly scrawled notes made from a conversation
over a bad connection, so bear with me,
I said that the Europeans didn't seem to use the term Fundulopanchax
for the big Aphyosemions; was this because of a reluctence to accept
Parenti's split of Ahyosemion, or was it justthat poeple are familiar
with the old name and change happens oh so slow. Andre replied
that it was a bit of both. On the one had, the heavyweights
that go collecting and do the descriptions - Woletjes, Wildekamp
Berkenkamp, Radda, don't agree with Parenti's paper; they have
their own classification as to how Aphysemion should be broken
up. He hinted that they would publish sometime in the next couple
of years, but that it might be a nasty battle. I made the point
that while Pareti's paper has yet been unopposed, Parenti is
a generalist, and knows a certain body of information about
family Cyprinodontidae as a whole, whereas Woeltjes, Wildekamp,
et al, had all made Aphyosemion their area of study; I suspect
they have more material and information about the Genus than
Parenti had access to. This should make for an interesting
resolution. On the other hand, even though Fundulopanchax
is for the moment, valid, there is still a great reluctence
among aquarists to adopt the new name - many people over there
are very good at keeping killies, but aren't as concerned
about the scientific aspects of it (like news.groups). Look
at this country where we still use ``Roloffia''. Although
this is less of a clear cut decision that Roloffia should
be abandoned, the official word 20 years ago was that
Roloffia (Clausen 1966) *is* invalid is reitierated by
Parenti in her paper of 1982 (84 ?) Yet there is still
a Roloffia class within the AKA, (in spite of the fact
that there is also a Fundulopanchax class :-) - Old
habits die hard - Roloffia is still almost universally
used. Go ahead, just ask for Chromaphyosemion occidentalis,
see if anybody knows what you're talking about. You'd have
better luck saying ``golden pheasent killie''.
Speaking of OCC, there is a new fish in that group. The
Germans ave described it as Roloffia huwaldi, but
people more interested in the science and less interested
in keeping Mr. Huwalds name on the fish consider it
to be a subpecies of OCC, viewing it as intermediate
between ocidentalis and toddi. This is backed up
somewhat by the fact that second and third generation
crosses with OCC and TOD are fertile. To their mind there should
be Aphyosemion (Chroaphyosemion) occidentalis occidentalis,
A. occidentalis toddi and A. ocidentalis huwaldi. Huwaldi
is a blueish fish, more like a blue occidentalis than
the somewhat stockier toddi. It is a new introduction;
the Germans just collected it last summer, and it should
be available (probably through the new and rare species
committee of the AKA) sometime next year.
A recent survey indicated there were 490 populations
of various species of killifish in Holland. This is
more than anywhere else in world. Not bad for a small
country :-) 70 species have been lost, but 80 new
ones are curently being maintained. Several of these
exist only in the hands of one person, but they
exist none the less.
Related to the taxanomical confusion (and I thought Apistogramma
was bad!) is the fact which Andre has recently discovered
that Aphyosemion (diapteron) bualanum, isn't. The fish which
is circulated as BUA was actually described by Ahl in 1924
as Aphyosemion alberti. The real bualanum is a much larger,
more robust, more red fish. Andre mentioned if he published
this he will get his head cut off; people have been using
BUA for 50 years. This confusion will come to light at
some point however.
There exists several study groups in Holland/Germany/France -
there is one for Fundulopanchax, one for the loussesnse (sp?)
and ogoense complex, one for the bualanum and exiguum complex, and
one for the cameronense complex. Andre is forwarding me the addresses
of each as there is definite interest in this country for
each of these groups.
Andre mentioned that one man kept nothing but bualanum, and
had 25 populations of it. I asked how he worked the logistics
of this, as having 4 tanks for each specie for breeding,
raising the fry and maintaining the adults would be over
100 tanks, and I know they are cramped for space over there.
Andre replied that for the easier species, such as
bualanum Ntui, the parents are left alone, and the fry
just pulled from the parents tank as they get large, whereas
with the new and rare species, they were artificially reared
bythe more conventional means of pulling the eggs an raising
the fry seperately.
*********
Which brings us to the question of inbreeding. The way killies
(and all other fish) used to be bred is a pair was selected
and bred. A pair was selected from their progeny, ad infinitum.
Invariably, the fertility of the breeding stock would suffer
or some other physical abnormality such as a bent spine would
manifest itself. There are two ways to get around this.
The first is to use a natural system, where at least three
pairs of adults in a heavily planted tank. Fry just automagically
appear, but only the quickest and most robust fry survive.
This circumvents the problem of fry being raised atificially
that in this circumstance (or in the wild) would not normally
survive. The number of matings between various males and
females is maximumized, also. Dr. Anthony C. Terceira
has reported keeping a colony of a BIV population in this
condition for 23 years, and Theo Steinfort has maintained
fish in this state for over 30 years wit no apparent
degradation. Inbreeding be dammned!
The other technique is an artifical setup in that pairs
are maintained as couples, but no less than three pairs
are used, and the female are swithced around so that
every male gets to breed with every female (a slightly
modified version just has 4 or 5 pair in a community
spawning situation). All the fry are raised together,
and the breeders are set up the same way as their
parents were. This maximizes the permutations and
combinations between the breeding stock, but still
leaves open the issue of which fish are allowed to reach
maturity. The Europens, having small tanks, cull ruthlessly,
much to the betterment of the species (the fish, not
the Europeans), thus, the problem is addressed.
After 3 generations, blood lines are swapped by
exchanging males or females with somebody else
who has the same population of the same species.
In a more practical vein, he still hasn't heard any
word of my shipment of wild SJO from Cameroon, and
he appears to be out of the Warri popuation of
SJO.
--
Surgical tools for mutant women
richard@gryphon.COM decwrl!gryphon!richard gryphon!richard@elroy.jpl.NASA.GOVdsill@ark1.nswc.navy.mil (Dave Sill) (10/25/89)
In article <21387@gryphon.COM>, richard@gryphon.COM (Richard Sexton) writes: > Which brings us to the question of inbreeding. Ah, that explains it. I knew there was something not quite normal about Richard. :-) Really, now that sci.aquaria is up for a vote, how about giving it a break? Dave Sill (dsill@relay.nswc.navy.mil)
alien@cpoint.UUCP (Alien Wells) (10/26/89)
In article <21387@gryphon.COM> richard@gryphon.COM (Richard Sexton) writes: >Speaking of OCC, there is a new fish in that group. The >Germans ave described it as Roloffia huwaldi, but >people more interested in the science and less interested >in keeping Mr. Huwalds name on the fish consider it >to be a subpecies of OCC, viewing it as intermediate >between ocidentalis and toddi. This is backed up >somewhat by the fact that second and third generation >crosses with OCC and TOD are fertile. To their mind there should >be Aphyosemion (Chroaphyosemion) occidentalis occidentalis, >A. occidentalis toddi and A. ocidentalis huwaldi. Huwaldi >is a blueish fish, more like a blue occidentalis than >the somewhat stockier toddi. It is a new introduction; >the Germans just collected it last summer, and it should >be available (probably through the new and rare species >committee of the AKA) sometime next year. I am glad to see that you at least said backed up 'somewhat'. The taxonomy of killies has always bothered me. To establish a new species, the standard criterion is the infertility of crosses between the population in question and all other species. This is generally a matter of genetic incompatibility. Allow me to spend a moment describing the mating behaviour of killies for those who might not be familiar. After appropriate courting rituals, the male killie physically grabs the female with the dorsal and anal fins. The anal fin of the male and the anal fin of the female are joined to form a tube which the eggs and sperm are simultaneously deposited into. The fertilization happens, then the fertilized eggs are let loose into the environment, generally either into the bottom mud or into foliage (breeders generally use peat moss or a 'mop'). The typical environment for killies is very acidic - and will kill any sperm that comes in contact with it before fertilization. The cross 'species' infertility of killies is generally caused by the failure of the anal fins to match into a perfect tube, allowing the acidic environment to intrude and kill off the sperm before fertilization. Thus, it is a physical, dimensional issue - not a genetic one. Experiments have shown that most 'species' of killies CAN be cross bred if they are stipped and the eggs are artificially inseminated. Furthermore, many 'species' that are infertile in the wild can be sucessfully cross-bred if they are put in an appropriate, non-acidic environment (although getting them to want to breed in that environment can be difficult). Many people have speculated that the physical, as opposed to genetic, nature of the cross-infertility can help explain the amazing diversity of killifish species. A very small mutation that changes the size, shape, or position of the anal fin - even by a small amount - can lead to a new population that cannot breed back into the parent population. However, this also causes some very bizarre possibilities. There is a case (I believe it is in the Andes) where populations of killies were taken at intervals all around a mountain. Every adjacent pair of killies could cross-breed. Pairs from across the mountain could not. Basically, there was a gradual shift of the geometry of the anal fins which would eventually become large enough to prevent fertile crossing. So, what am I trying to say? (I apologize for my long-windedness.) Only that I smile whenever I hear the furious debates about the taxonomy of killifish (the debates about what to name new newsgroups are tame by comparison). I may be branding myself heretic, but I feel that the current way of classifying killifish is fundamentally flawed. I also feel that any correction of the situation is going to be a major research project. My feeling is that the taxonomy of killifish should be extended from 2 levels to 3, with the second level being genetic infertility and the third being physical infertility. I'm quite aware, however, that this is a rather controversial proposal in what is a rather conservative field (ie: taxonomy). In the mean time, is is very important for breeders to continue what they are doing, which is coming up with some method of classification and keeping the populations pure. Regardless of how you feel about the taxonomy, it is important to make every reasonable attempt to keep the strains true to what they are in nature. -- --------| You've got the political savvy Alien | of a hangnail. --------| - John Meneghini decvax!frog!cpoint!alien bu-cs!mirror!frog!cpoint!alien
richard@gryphon.COM (Richard Sexton) (10/27/89)
In article <193@ark1.nswc.navy.mil> Dave Sill <dsill@relay.nswc.navy.mil> writes: >In article <21387@gryphon.COM>, richard@gryphon.COM (Richard Sexton) writes: >> Which brings us to the question of inbreeding. > >Ah, that explains it. I knew there was something not quite normal >about Richard. :-) > >Really, now that sci.aquaria is up for a vote, how about giving it a >break? Dear Mr. Sill; Inasmuch as I have received and reviewed your request for me to stop inbreeding, I'm afrain I have to reject your request as I intend to inbreed until it kills me. Thanks very much for your concern, however, Sincerely, Richard J. Sexton -- ``They care more about the name than the content? Amazing.'' - Mark R. Horton richard@gryphon.COM decwrl!gryphon!richard gryphon!richard@elroy.jpl.NASA.GOV