Conference Paper
The evolution of temperature preference in the mexican cave fish Astyanax mexicanus
Tabin, J., Rohner, N., Haro, A., Kowalko, J., Martineau, B., Borowsky, R. and Tabin, C.
Record Number:
3251
Year:
2017
Journal:
AIM 2017
Abstract:
Even though a human can survive equally well in both fifty degree weather and seventy
degree weather, why is it that most would prefer to be in the latter? Everybody has preferences,
but not much is known about the genetics of preferences or how they evolve. We have been
studying the temperature preference of Astyanax mexicanus populations from different caves and
of the surface population living in adjacent rivers. In principle, the temperature in the caves
differs from, and is more stable than, the temperature in rivers, which could lead to selection for
different preferences. We are in the process of measuring the actual temperatures throughout the
year at a series of caves and the adjacent rivers in Mexico. It would make sense that the caves
have different temperatures, as we have indeed found that the cave populations have different
temperature preferences. For example, the Pachon fish distinctively like cooler temperatures than
the surface fish. Genetic analysis indicates that these are inherited traits. Analysis of F2s suggest
that the trait is not Mendelian but rather is more complex. We inadvertently discovered a second
type of temperature preference in these populations when our colony was transiently afflicted
with parasites (gill flukes). The parasites had the effect of making the fish prefer warmer
temperatures (akin to a fever response in humans). However, this effect was found to be
significantly less pronounced in the cave fish than the surface fish. We are now attempting to
map the genes underlying temperature preference in Astyanax by QTL analysis, the results of
which will be discussed.
Times Cited:
1
Relevent Species: