The different potential fitness outcomes between reproduction by cloning or by sex have puzzled researchers for years. But whatever the reason for the two quite different strategies, most species have evolved to use one or the other, or a fixed pattern of both. But new work on a brittle star, a marine invertebrate, suggests that at least this one species may be able to choose one or the other r...

The properties of tectonic earthquake sources are compared with those deduced here for fault planes in solid neutron-star matter. The conclusion that neutron-star matter cannot exhibit brittle fracture at any temperature or magnetic field strength is significant for current theories of pulsar glitches, and of the anomalous X-ray pulsars and soft-gamma repeaters. Subject headings: stars:neutron ...

BACKGROUND There are five major extant groups of Echinodermata: Crinoidea (feather stars and sea lillies), Ophiuroidea (brittle stars and basket stars), Asteroidea (sea stars), Echinoidea (sea urchins, sea biscuits, and sand dollars), and Holothuroidea (sea cucumbers). These animals are known for their pentaradial symmetry as adults, unique water vascular system, mutable collagenous tissues, an...

In traditional medicine, extracts of polysaccharide-containing plants are widely employed for the treatment of cutaneus wounds. The brittle star, as one of marine organisms, encompasses bioactive compounds, which confer the healing potency of damaged arms. The aim of the present study is to investigate the effects of extracted polysaccharide from the Persian Gulf brittle star )Ophiocoma erinace...

Many plant and animal species reproduce both sexually and asexually. These 2 reproductive modes are both likely to be costly and, in many species, they occur at different times of the year. Here, I present information on the sexual and asexual reproductive biology of the brittle star Ophiactis savignyi (Echinodermata, Ophiuroidea) in the Florida Keys, USA. Small brittle stars (less than 3 mm) a...