Journal Article
Evolution of a behavioural shift mediated by superficial neuromasts helps cavefish find food in darkness
Yoshizawa, M., Goricki, S., Soares, D. and Jeffery, W.R.
Record Number:
2955
Year:
2010
Journal:
Current Biology
Pages:
1631-1636
Volume:
20
Abstract:
How cave
animals adapt to life in darkness is a poorly understood aspect of
evolutionary biology. Here we identify a behavioral shift and its
morphological basis in Astyanax mexicanus, a teleost with a sighted
surface-dwelling form (surface fish) and various blind cave-dwelling
forms (cavefish). Vibration attraction behavior (VAB) is the ability of
fish to swim toward the source of a water disturbance in darkness. VAB
was typically seen in cavefish, rarely in surface fish, and was
advantageous for feeding success in the dark. The potential for showing
VAB has a genetic component and is linked to the mechanosensory
function of the lateral line. VAB was evoked by vibration stimuli peaking
at 35 Hz, blocked by lateral line inhibitors, first detected after
developmental increases in superficial neuromast (SN) number and size,
and significantly reduced by bilateral ablation of SN. We conclude that
VAB and SN enhancement coevolved to compensate for loss of vision
and to help blind cavefish find food in darkness. Highlights: Vibration
attraction behavior (VAB) was characterized in blind cavefish; VAB has
a genetic basis and confers an advantage for feeding in darkness; VAB is
based on an increase in superficial neuromasts (SN); Coevolution of VAB
and SN was likely a critical step in adaptation to cave life
Times Cited:
1
Relevent Species: