Previous research confirmed that the worms' behavior is controlled by their brains, but it's possible that some of their memories may have been stored in their bodies, or that the training given to their initial heads somehow modified other parts of their nervous systems, which then altered how their new brains grew.
We show that worms exhibit environmental familiarization, and that this memory persists for at least 14 days – long enough for the brain to regenerate.
A memory worm, also rendered Memory Worm, was an alien worm that could remove the memories of those it touched.
(July 18, 2013) -- Tufts University biologists using new, automated training and testing techniques have found that planarian flatworms store memory outside their brains and, if their heads are removed, can apparently imprint these memories on their new brains during regeneration.
Five species of worms were documented regrowing heads and brains: four of them seen doing so for the first time, and one that was previously known for head regeneration. In addition, the researchers found further evidence in earlier studies of head-growing in three more ribbon worm species.
Almost all worms can regrow their tails if they are amputated, and many earthworms can lose several segments from their head end and they will grow back, the Washington Post reports. For some worms, however, the more segments that are cut off, the less likely they are to be fully regenerated.
They might sense something, but it is not painful and does not compromise their well-being." The government called for the study on pain, discomfort and stress in invertebrates to help in the planned revision of Norway's animal protection law.
Despite having species in almost all aquatic habitats, flatworms are most commonly found on the surfaces and undersides of rocks in slow moving water. Most species of freshwater flatworm are at least moderately tolerant of polluted conditions.
Platyhelminthes do not have a heart, lungs, or blood vessels. As such, they lack circulatory systems, instead relying on passive diffusion for obtaining the oxygen they need for cellular breathing.
Planarian worms and their stem cells are somehow able to avoid the ageing process and to keep their cells dividing.” One of the events associated with ageing cells is related to telomere length. In order to grow and function normally, cells in our bodies must keep dividing to replace cells that are worn out or damaged.
In earthworm, cerebral ganglions function as a simple brain which is located above pharynx and is connected to the first ventral ganglion the removal of which would result in uncontrolled movement of the worm. Neuronal and reflex pathways control the coordinated movements and behavior of the worms.
Cerebral ganglion
The earthworm's 'brain'. Earthworms have a simple nervous system. The cerebral ganglion is connected to a ventral nerve cord that runs the length of the body. Each segment is connected to this cord, allowing earthworms to move and respond to light, touch, chemicals, vibrations and more.
Worms have a really, really keen sense of taste and smell, they can differentiate between thousands of individual smells and tastes just in their 300 brain cells.
Elephants, cats, flies, and even worms sleep. It is a natural part of many animals' lives. New research from Caltech takes a deeper look at sleep in the tiny roundworm Caenorhabditis elegans, or C. elegans, finding three chemicals that collectively work together to induce sleep.
Biologists at Princeton have shown that in worms, learned behaviors can be passed down as many as four generations, with younger worms instinctively avoiding bacteria they've never encountered themselves.
Worms do not have eyes but they can sense light, especially at their anterior (front end). They move away from light and will become paralyzed if exposed to light for too long. A red worm is moist to the touch because of a slimy coating which keeps it from drying out. If a worm's tail is cut off it will grow back.
The Gallio research team found that planarians possess their own variant of an already famous receptor, the transient receptor potential ankyrin 1 (TRPA1). TRPA1 is best known as the "wasabi receptor" in humans and as a sensor for environmental irritants giving rise to the sensation of pain and itch.
Don't be fooled though, they make up for it with the interesting aspects they do have. Like five hearts that squeeze two blood vessels to push blood throughout their little bodies. Earthworms have mucus and little hairs covering their skin that allows them to move through different types of soil.
All flatworms (Phylum Platyhelminthes) are hermaphrodites in that they have both male and female reproductive organs. All flatworms can either give or receive sperm, i.e. they can be either the male or the female in a pair (Rawlinson et al. 2008).
These flatworms have both fully functional male and female reproductive capabilities that can be used interchangeably, unlike other hermaphroditic species who switch back and forth during different phases of life.
Among the free-living flatworms, some reproduce exclusively by sexual reproduction and others by asexual reproduction (reviewed in Henley, 1974). Others can switch between sexual and asexual reproduction, depending on the environmental circumstances.
The flatworm (phylum Platyhelminthes) are simple animals that lack circulatory, respiratory, and endocrine systems found in other bilaterally symmetric animals, and yet they sleep and possess a bilobal brain.
A web site for fans of earthworms tackled the question recently: Yes, it is now accepted that worms feel pain – and that includes when they are cut in half. They do not anticipate pain or feel pain as an emotional response, however. They simply move in response to pain as a reflex response.
However, earthworms can survive if their tail end is cut off, and can regrow their segments but earthworms generally cannot survive if the front part of their body between the head and the saddle is cut as this is where their major organs are.
Thinking and feeling: Worms have a brain that connects with nerves from their skin and muscles. Their nerves can detect light, vibrations, and even some tastes, and the muscles of their bodies make movements in response.