Weird Science Weekly: Decapitated worms can regrow memories along with their heads

Scott Sutherland

Weird science happens all around us, every day. In this instalment of Weird Science Weekly, I gather some of the past week's strangest examples, such as worms that can regrow memories along with their head, synchronized singer heartbeats and sharks who hunt with their tails.

Worms can regrow memories to go with regrown heads

You might remember the schoolyard rumor that when you cut a worm in half, tada, you get two worms. It's worth saying, before I go any further, that the rumor isn't true — at best you'll end up with one short worm and, more likely, you'll just have two pieces of one dead worm. However, we do know certain worms have regenerative properties, and researchers at Tufts University revealed this week that some of them can regrow more than just body parts.

Scientists have known for a while that planarians, or flatworms, have the ability to grow back functioning heads and brains after they're decapitated. It was a series of somewhat bizarre experiments back in the 50s, which have been thoroughly debunked by now, that helped inspire new tests at Tufts that have turned up some remarkable results.

The authors of the study, recently published in The Journal of Experimental Biology, first trained worms to associate the feel of the dishes they lived in with nearby food. They also worked to overcome the animals' natural aversion to light, by encouraging them into a brightly-lit section of their dish in search of dinner.

Then, it was off with their heads.

When put back in the same conditions after their two-week head-regrowing recovery, the worms and their new brains still seemed to remember the signals their old heads had learned. The worms who had been trained to go into the light also seemed to remember their teachings.

Which begs the question — how? The researchers aren't sure yet. It's possible memories are being stored elsewhere in the worms' bodies, or that the training somehow modified their nervous systems, which in turn altered their new brains as they grew. Another possibility is what's known as epigentics — the idea that an organism's genome can be modified to include certain memories in the worms' DNA.

Whatever it is, let's hope they don't remember the part where we cut their heads off!

[ Related: Weird Science Weekly: Sperm have a sweet tooth ]

Study shows choir members' heartbeats synchronize

Who needs a metronome when you can rely on the rhythmic heartbeats of all the singers?

Researchers from Sweden released findings this week that show singing in a choir has a calming effect on the heart. The study, published in Frontiers in Psychology, examined the effect of different song structures on the heart rate and respiration of a high school choir. They were asked to hum, sing and breathe freely, as well as to sing a slower mantra with specific intervals for breathing.

They found that singing a structured song in unison coaxed the choir's heartbeats into the same rhythm, hearts accelerating and decelerating at the same time. The leader of the project, Bjorn Vichoff, told NPR that "the readout from the pulse monitors starts as a jumble of jagged lines, but quickly becomes a series of uniform peaks. The heart rates fall into a shared rhythm guided by the song's tempo."

Gives a whole new meaning to the phrase "all together now."

Thresher sharks hunt with tails, may be smarter than we thought

They're probably still not smart enough to beat your wife's plane to the Bahamas, but new underwater footage shows that thresher sharks are capable of the kind of intelligent hunting behaviour we usually only associate with aquatic mammals.

Scientists at the Thresher Shark Research and Conservation Project captured the sharks using their tails to attack schools of sardines in the Philippines. Each swipe of their tail can take out up to seven sardines, both by physically hitting the smaller fish and with the ensuing shockwave. That leaves the tasty morsels separated from their school and easy for the sharks to snap up.

[ Related: Weird Science Weekly: Baby chickens are smarter than children ]

Teen scientist develops bioplastic from discarded banana peels

As part of the Google Science Fair, Scientific American sponsors an award for 'Science in Action', awarding a project that aims to make an immediate impact on the environment, health or resource challenges. This year's winner, 16-year-old Istanbul-native Elif Bilgin, has developed plastic from discarded banana peels, working off of the fact the peels (and some other fruit skins) contain starch and cellulose, used elsewhere in the bioplastics industry. You might be familiar, for instance, with Spudware, the disposable cutlery made from potatoes. Bilgin explains the process and her findings in the video portion of her entry:

Bilgin is also a finalist for the overall Google Science Fair prize, which will be decided in September. You can read more about her entry on the science fair site itself. Kids these days, huh?

Vaccinated children help to protect their grandparents

It may seem counter-intuitive, but making sure your children are vaccinated against blood and ear infections can help keep your parents out of the hospital, too. A study funded by the Centers for Disease Control and published in this week's New England Journal of Medicine concluded that the 'herd immunity' of the children is also reducing the spread of pneumonia to the rest of the population, and to older adults in particular.

Herd immunity refers to the fact that vaccinating a large portion of the population makes it less likely a non-immune individual will come in contact with an illness, and therefore the illness is less likely to spread.

In the case of this study, researchers were checking up on the impact of a pneumococcal vaccination that was introduced to the suite of standard shots for children in the U.S. in 2000. While they discovered that, as expected, the rate of hospitalization for childhood pneumonia continued to decline after the introduction of the vaccination, they were pleasantly surprised to discover that the rate of hospitalization in older children and adults declined as well, even though they hadn't received the shot.

The study authors are quick to point out that other strains may expand to fill the void left by the bacteria controlled by the vaccination, so it remains important to continue these types of studies. However, considering pneumonia is responsible for 350,000 to 620,000 older adults in the U.S. being hospitalized each year, and a yearly pneumonia shot, much like the flu shot, is recommended for older adults, a little bit of extra help from the youngsters couldn't hurt.

[ More Geekquinox: Hubble telescope sees true blue colour of nearby alien planet ]

Keep your eyes on the wonders of science, and if you spot anything particularly strange you'd like me to check out for next week, comment below or drop me a line on Twitter!

(Photo credit: Journal of Experimental Biology/Shormat and Levin)

Geek out with the latest in science and weather.
Follow @ygeekquinox on Twitter!