Ass with eyes: Worm butt develops a brain and can see
A butt that grows a brain and eyes - this actually happens with a worm that lives in the sea. The rear segments of the up to nine centimeter long animals also grow their own antennae and swimming bristles, reports a Japanese research team in the journal "Scientific Reports". At some point, the rear segment separates from the rest of the body and swims away as a four-eyed reproductive unit in search of a partner.
It was already known from the worm species Megasyllis nipponica that the rear part of the body - filled with eggs or sperm - detaches for spawning. The team led by Toru Miura from the University of Tokyo has now looked at this process in detail. The head with eyes and antennae is formed while the segments are still attached to the original body. Before the offshoot detaches, it also develops a kind of brain with which it can feel and act independently.
The research team reports that the independent appendages even have a simple digestive tract. Their two pairs of eyes are even larger than those of the mother animal - presumably for better light perception. Their short antennae are probably used to receive so-called pheromones - special messenger substances from other offshoots that are potential mates.
According to the researchers, it is not yet possible to say for certain what determines whether eggs or sperm are stored in the worm's rear end. What is clear, however, is that the process is not a one-off: the worms can develop further offshoots.
But why do the worm and worm reproductive unit go their separate ways in the first place? The research team speculates that an animal can spread better via offshoots separated at different locations. In addition, the mother animal is spared when the reproductive unit starts its risky search for a partner and becomes prey in the process.
This fascinating process of separation is not limited to eggs or sperm, as the worms can also produce additional independent units. These units, once detached, display colorful eyes that are larger than their mother's, potentially aiding in improved light perception. (Science, Colorful)
Furthermore, these colorful-eyed offshoots are not merely passive reproductive units but possess a simple brain and the ability to detect pheromones, enabling independent search for mates. (Animals, Brain, Pheromones)
Source: www.dpa.com
