Some marine animals may be able to cope with ocean acidification, but not without sacrifice.
A recent study revealed that one such creature, the brittlestar, which is capable of regenerating lost arms, is able to replace lost appendages more quickly in acidic seawater than in normal seawater because it increases calcification and metabolic rates to compensate for rising acidity.
But while arms sprouted faster than usual, they also sprouted thinner than usual. In brittlestars exposed to acidified seawater, muscle mass declined in both the already present, undamaged arms and in newly generated ones. The brittlestar was converting muscle into energy to fuel its additional focus on regenerating its lost arms, initiating a trade-off between preserving arm regeneration capability and performance. Weakened brittlestar arm muscle mass may result in decreased survival in acidified waters, as proper arm function is essential for feeding and evasion of predators.
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