Xxx cam split

Lybia gain both nutritional and protective benefits from their sea anemones (Duerden, 1905; Karplus, Fiedler & Ramcharan, 1998; Schnytzer et al., 2013).

Although crab-cnidarian associations are generally characterized by a small crab and a larger cnidarian associate who is regarded as the clear host (Thiel & Baeza, 2001), in this case, the crab is the larger of the two associates, making the host-symbiont identification harder to define. However, in the Red Sea they are only found holding Alicia sp. When deprived of their sea anemones, the crabs make no use of their delicate claws but use their first walking legs, and sometimes the second and third ones, for the gathering of food and other behaviors usually performed by the claws (Duerden, 1905; Karplus, Fiedler & Ramcharan, 1998; Schnytzer et al., 2013).

If the crabs in nature behave like those observed in the laboratory, namely, frequent “splitting” and theft of sea anemones, we would expect to see high levels of genetic identity between each sea anemone pair.

The ultimate aim of this study is to explore splitting and intraspecific theft, which forces asexual reproduction, consequently leading to reduced genetic variability in sea anemones held by boxer crabs.

In the present study, we examined three hypotheses: (1) the pair of sea anemone held by a crab is an outcome of splitting a single sea anemone; (2) crabs deprived of sea anemones will steal a whole sea anemone, or fragment, from a conspecific organism; (3) these interactions affect the genotype structure of field populations of sea anemones.

To test these hypotheses, we conducted behavioral experiments intended on empirically testing the anecdotal reports of sea anemone “splitting” and intraspecific theft.

The sites were approximately 3 km apart, Tur-Yam (29°31′49.69N; 34°55′36.39″E) and Red Rock Beach (29°31′01.40″N; 34°55′13.34″E). Using a small hand-held net, the crabs were collected and then individually placed in 0.5 L bottles filled with fresh sea water from the collection site, kept in a thermally insulated box and transported to Bar-Ilan University, Ramat Gan, Israel.

The animals were collected and maintained within the guidelines of the Israel Nature and National Parks Authority (Permit no. For the splitting experiment, each of the crabs had one sea anemone removed.

The occurrence and mode of asexual propagation, whether via budding, fission, pedal laceration, or apomictic parthenogenesis, varies among families, genera, and even sister-species within the same genus (Chia, 1976; Francis, 1988; Shick, 1991), suggesting that asexual multiplication has a complex evolutionary history among sea anemones (Mc Fadden et al., 1997).Laboratory observations showed that the removal of one anemone from a crab induces a “splitting” behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism) it was shown that each pair of anemones from a given crab is genetically identical.Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the “theft” of a complete anemone or anemone fragment by the crab without them. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences.Individuals of Lybia leptochelis and their symbiotic sea anemones Alicia sp.were collected from the shallow infra littoral zone at two separated beaches in Eilat, Israel during 2007–08 and again during 2013. Female crabs were observed carrying eggs from 4 mm carapace width (CW; Y Schnytzer, 2008, unpublished data), and therefore female crabs at least this size were defined as adults. The sea anemones held by the crabs were ≤2.5 mm pedal disc diameter (PDD).

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