All DNA tests on the electric blue Jack Dempseys so far indicate that the fish are not hybrids.
each male and female Jack Dempsey, and
then did the same for each male and female
electric blue Jack Dempsey. In less than a
week after sending them to Dr. Price, he
emailed me to let me know the results were
in and sent me his conclusion. These are
his exact words:
I have finished the experiment
and I see no evidence for the EB
being a hybrid. This confirms what
you said Chakrabarty told you.
I find exactly the same single
sequence from each of the four
samples you sent. There is no hint
in the EB samples of a second
sequence that could have come
from another species.
As clearly stated, the results show all
samples were a match. These samples also
matched R. octofasciata samples already on
file in the GenBank database from previous
DNA sequencing. What he neglects to tell
us, however, is that these samples are a
match only in regards to the gene region
targeted, an intron in the S7 ribosomal
protein gene, therefore these results cannot
be read as conclusive.
Remaining Questions
Why would we target such a small
portion of the entire genome? It was
targeted simply because these sequences
could already be found for R. octofasciata,
as well as all other suspected parental
species within the GenBank. We needed
something for comparison, and it would
have been foolish to sample regions we had
nothing to compare with.
So while this is another test that shows
the electric blue Jack Dempsey is likely not
a hybrid, it does not prove so conclusively.
This means a lot more has to be done,
meaning more time logged in the lab and
more money spent to get better answers.
Other tests can be run, such as karyotyping,
to try and get a sense of the ploidy, or
chromosome count. My guess, however,
is that no matter how many tests are run,
and no matter how many hours are logged
in the laboratory, skeptics will always be
doubtful of the color morph theory.
Hybrid theorists hold firm on their end
of the debate and will rightfully do so
until a complete genome mapping of all
suspected parental species are laid out in
front of them. This is a task of monumental
proportions. To undertake such a project
would likely cost tens of thousands of
dollars, and it could take many years to
complete.
The only thing that would get this done
quicker and cheaper, while maintaining
the integrity and precision of the tests,
would be to use a major university, with
its federal funding and state-of-the-art
facilities. Together with their students—if
properly motivated, of course—a professor
could guide his class through a year-long
process of complete genome mapping. It’s
a worthy project, one that could bring
plenty of attention and make a graduating
Tony Terceira
These young blue Jack Dempseys exhibit some of the golden coloration of the original form.
88
www.tfhmagazine.com
August 2009