( kly tidal cycle.?/p> “Wide burrows sp...)Biologist Discovers What May Be World’s ‘Pickiest?Mates

“Wide burrows speed incubation, so cause the larvae to hatch too early and miss the peak tides. This research provides one of the first examples of how choosy resource selection can help offspring survivorship.?/p>

Male fiddler crabs attract suitors by standing in front of their burrows and waving their enlarged claws at prospective female passers by, much as humans motions “come here?with their arms and hands

“The California fiddler crabs use a lateral wave that looks much like a human beckoning 'come here??deRivera said. “It also seems to serve as a 'come hither' signal, as a male waves, standing at his burrow entrance, and interested females come over.?/p>

Interested females initially eye the males, who select their burrows based upon their body size, and if they’re interested, partially or fully enter a burrow to size it up.

“The burrow openings, which are circular, are just big enough for the owners to get in,?deRivera said. “Crabs enter burrows sideways so have to fit in front to back and top to bottom.?/p>

When a female has found a mate and burrow to her liking, typically one that is about the same size as she, either she or the male will plug up the opening of the burrow and the couple will mate and incubate their eggs, which later hatch and release tiny crab larvae that are quickly flushed from the estuary by high night tides.

deRivera found that larger female crabs couldn’t be as picky about choosing mates as their smaller counterparts. They took less time, she noted, because they entered fewer burrows, primarily because many of the burrows they passed were too small to accommodate them and successfully incubate their eggs and release their larvae.

“Larvae were successfully released during high-amplitude nocturnal tides only when females incubated in burrows that allowed the larvae to exit the estuary swiftly and thus reduce predation risk, but not when females incubated in burrows that w
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Source:University of California, San Diego