Fig. 2. (A) Plasma concentrations of Na+ (solid bars) and
Cl– (hatched bars) in killifish decrease after transfer from
brackish water (BW, 10% seawater; grey bars) to fresh water (FW; black bars)
and recover slowly thereafter. (B) Plasma cortisol concentrations increase
transiently as a result of transfer to freshwater, compared to both
pre-transfer and time-matched BW controls. Values are means ± s.e.m.
(N
6). *Significant difference from pre-transfer (Pre) brackish
water control (P<0.05). 
Significant difference
between time-matched FW and BW groups.