richtersi The first lab oviposition of mature females collected

richtersi. The first lab oviposition of mature females collected in the field in the spring and fall as well as cohorts of eggs laid by females born in the laboratory were used. The eggs of all samples, maintained under the same constant experimental conditions, had a high hatching percentage (from 75 to 93%) but a high variability occurred in the hatching time. Four patterns were identified. First, subitaneous eggs hatched within 30–40 days from oviposition. Second, delayed-hatching eggs hatched gradually MK-1775 cell line over 41–62 days.

Some eggs did not hatch within 90 days from oviposition when water was maintained in the culture. Within this group, 13% of eggs (diapause resting eggs; third category) do not hatch until they are subjected to desiccation,

followed by rehydration, while 87% never complete their development (abortive eggs; fourth category). The four categories of eggs had no morphological differences. The high variability in the hatching time of tardigrade eggs might be considered a form of bet-hedging. “
“In November 2002 the Prestige tanker spilled 59 000 tonnes of oil off Galicia (north-west Spain) and contaminated a vast coastal area extending from northern Portugal to Brittany (France). Two study areas, a coastal lagoon (1 sample point) and a stretch of rocky coast (includes 5 sample points), were selected to examine changes on the diet of otters Lutra lutra L. before 上海皓元 and after the oil spill. Diet was assessed from 1103 spraints, 553 collected in 2000, before the spill and 550 in 2003, after the spill. In the coastal ITF2357 cell line lagoon, after spill, spraints contained more shrimp (Palaemon sp.), more prey of marine origin, and fewer gobies (Pomatoschistus sp.) and eels Anguilla anguilla. A decline of the eel population in the coastal lagoon may have caused otters to make more frequent visits to the sea. On the rocky coast, spraints contained more blennids in 1 of the 5 sampling points, however, the seasonal patterns of the principal prey species (Blennidae, Gadidae and Labridae)

were similar across the 2 years of study. The differences may be attributed to common interannual variations in the diet of marine otters, but the design of this study cannot assess the degree of natural variation in the diet of coastal otters before the oil spill. “
“It has been proposed that sympatric bumblebee species form mimicry rings to profit from learnt avoidance behaviour by predators. This hypothesis can be tested by comparing the predation rates of local bumblebees with those of imported non-native bumblebees, whose coat colour is different from that of local bees, so that their coloration is unfamiliar to local predators. To test whether populations of non-native bumblebees suffer higher worker loss rates during foraging, we conducted transplant experiments in the UK, Germany and Sardinia.

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