Switch it up
Toasty temperatures trump genetics
when it comes to the sex of a bearded
dragon lizard ( 1). Now researchers have
found how RNA editing helps turn overheated male embryos into females (SN
Giant larvaceans don’t have noses,
but they sure know how to blow snot
bubbles. The sea invertebrates live in
disposable “mucus houses” that, based
on recent observations, collect food fast.
When these larvaceans ditch a dirty
house and “sneeze” themselves a new
one, they might send a lot of carbon to
the deep sea (SN: 6/10/17, p. 13).
Blood and guts
Antarctic-dwelling sea spiders ( 2) use
their long legs for more than creepy-crawling below the ice. Stretches of
digestive tract in the creatures’ legs do
double duty — not only digesting meals,
but also pumping an arthropod version
of blood and oxygen through the rest of
the body (SN: 2/4/17, p. 13).
South American polka dot tree frogs are
the first amphibians known to naturally
fluoresce. The frogs’ intense blue-green
glow might play a role in complex courtship and fighting behaviors, biologists
propose (SN: 4/15/17, p. 4).
Brainless beauty sleep
Upside-down jellyfish are the first brainless animals known to catch some z’s,
lab experiments suggest (SN: 10/28/17,
p. 10). The finding raises new questions
about when and why sleep evolved.
Pachyderm power nap
For some wild elephants, a good night’s
sleep ends soon after it starts. Electronic
monitoring of two African elephants
found that the animals snooze about
two hours per day — the shortest sleep
requirement recorded for mammals
(SN: 4/1/17, p. 10).
Chop off a hydra’s head, and two more
grow in its place — or so the ancient
Greek myth goes. By fiddling with the
cytoskeletons of real-life hydras, researchers found that the pond polyps rely
on mechanical forces as well as molecular
cues to regenerate head and tentacles in
the right places (SN: 3/4/17, p. 19).
Flamingos may be more stable standing on one leg than two, especially
when asleep, researchers reported (SN:
6/24/17, p. 15). The blushing bird’s center
of gravity is located near its tucked-in
knee, which helps with stability. A one-legged stance requires little muscular
effort, the scientists say, but others caution that it may not be an energy saver.
Tardigrades ( 3) are known for withstanding extreme temperatures, intense
radiation and even the vacuum of space.
Those adaptations could help this hardy
lineage survive until Earth is engulfed by
the sun in several billion years, researchers estimate (SN Online: 7/14/17). An
analysis of the microscopic water bears’
genetic blueprints offers clues to their
survival strategies, and challenges
claims that tardigrades are extreme
gene swappers (SN: 8/19/17, p. 13).
Paint it blue
Scientists borrowed a gene each from
Canterbury bells and butterfly peas
to breed the world’s first true blue
chrysanthemums ( 4). The method could
be used to give other flower species the
blues (SN: 8/19/17, p. 12).
— Cassie Martin
Life finds a way
2017 revealed some surprising biology of organisms large and small, from
quick-dozing elephants to sex-changing lizards and carbon-dumping sea creatures.