DIGEST
In the Paris Zoo, near lions, tigers and bears,
lies an organism that precedes humans on
Earth by some 500 million years. The yellow,
sponge-like being has neither neurons nor a
brain, yet it has the potential to revolutionise
our understanding of intelligence.
The remarkable single-celled amoeba
is called a slime mould, affectionately
nicknamed “the blob”. It slowly covers
ground in search of prey by extending finger-
like protrusions called pseudopods.
Slime moulds have been known to solve
mazes by “remembering” the
dead ends. In one study,
given nutrient“station” points, they recreated a Tokyo rail
system map more efficiently than its actual
construction.
“Le blob” has sent a “big wave of visitors”
through the gates of Paris Zoo, according
to spokeswoman Vanessa Leroy. But these
organisms are more than just a zoo exhibit.
Audrey Dussutour of France’s National
Center for Scientific Research was drawn to
discover their full capabilities. Could slime
moulds habituate against substances they
would normally avoid?
Dussutour placed dishes of oatmeal a
short distance away from a slime mould. To
reach its tasty meal, the mould had to grow
across gelatin bridges laced with harmless
but bitter chemicals. In the first experiment,
it took 10 hours to cross the bridge.
However, after just six days the
slime mould began ignoring
the deterrent. It had
learnt.“That such organisms have the capacity
to learn has considerable implications,” says
Dussutour.
A follow-up study revealed that slime
moulds could also share learnt information
via cell fusion, and remember their
habituation after a year of hibernation.
These studies have drawn considerable
attention to these otherworldly creatures.
Leroy explains that visitors are bursting
with curiosity when confronted by the
unknown organism. “People take the time
to look at the real specimen,” she says.
“Presentations are followed by many people,
who ask more questions than usual.
“Questions go from very basic such
as, ‘Is it dangerous?’, ‘Can it be eaten?’,
to very specific questions from fanatics
or scientists, such as ‘Has its genome
already been sequenced?’ or, ‘Have
hybrids been produced and what are their
characteristics?’,” Leroy says.
With research on this curious organism
far from finished, le blob has been guaranteed
permanent accommodation at the Paris Zoo.
“The zoo, as part of the National Museum
of Natural History, is actively involved
in research, and the blob is of course
a primary subject,” says Leroy.
“So we plan on presenting in
the exhibit results and future
directions of such studies.”- ELLIE GRIFFIN
Action in amber
Fossil reveals 16-million-year-old
hitchhikers.How did tiny crawling soil dwellers get
around during the early Miocene? If this
snapshot in amber from the Dominican
Republic is anything to go by, they
hitchhiked.
The fossil reveals a number of tiny
arthropods called springtails (Collembola)
still attached to the wings and legs of a large
winged termite, while others are gradually
floating away from their host.
In a paper in the journal BMC
Evolutionary Biology, researchers from the
New Jersey Institute of Technology (NJIT),
US, and Muséum national d’Histoire
naturelle, France, say the discoveryhighlights the existence of a new type of
hitchhiking behaviour among wingless soil-
dwelling arthropods.
It also could help explain how
symphypleonan springtails (one of three
main groups) achieved dispersal worldwide.“The existence of this hitchhiking
behaviour is especially exciting given the
fact that modern springtails are rarely
described as having any interspecific
association with surrounding animals,” says
NJIT’s Ninon Robin. – AMELIA NICHELEPALAEONTOLOGY
N. RUBIN, C. D’HAESE & P. BARDEN; GETTY