Several cycles of reproduction
Date: August 16, 11:00
Researchers at the University of Warsaw have discovered that overfeeding microscopic flatworms Stenostomum with unicellular organisms containing green algae triggers multiple cycles of reproduction simultaneously. This leads to the temporary connection of individuals into chains of four to five clones, which the researchers have dubbed 'paracolonies'. These structures are not permanent and separate after the development of a new head, however, the overall advantages of such existence have not been confirmed, aside from the possible increase in overall body size.
Process of chain formation
During experiments, scientists studied four species of freshwater worms Stenostomum. It was found that a large amount of food causes worms to simultaneously initiate several cycles of reproduction. Typically, Stenostomum reproduce without mating: a new head and part of the body are formed inside the body, after which the young worm separates. The process of chain formation begins after feeding on unicellular freshwater organisms that contain green algae. Researchers noted that the more such food the worms received, the more often they formed chains.
- The first signs of a new head in the worms appeared approximately two days after feeding began.
- After four days, the longest chains consisted of four or five connected individuals.
- When the oldest new head completes its development, the worms separate into smaller groups or individual specimens.
Researchers found no evidence that connected worms shared food digestion. In one experiment, chains of one species were less frequently preyed upon by predators, but for another species, no such effect was found.
Zoologist at the University of Warsaw, Ludwik Gonsiorowski, suggested that potential advantages might be related to the increase in overall body size, rather than multiple heads. Structures were also observed in other species, such as Catenula lemnae, where chains could consist of more than 15 connected parts. In another related species, up to 50 connected parts were recorded. Researchers suggest that permanent chains of related worms could have emerged from a similar mechanism triggered in Stenostomum by an excess of food. However, the hypothesis regarding the origin of permanent chains has yet to be verified.
Source: Science Alert
These findings may have significant implications for further study of the mechanisms of reproduction and evolutionary adaptations in invertebrates. In particular, understanding how environmental factors, such as food availability, can influence the behavior and physiology of these organisms may help in developing new strategies for conserving species diversity and managing ecosystems. Investigating such mechanisms may also open new horizons for studying clonal reproduction in other organisms.