2017 delivered amazing biology finds from organisms large and small

From elephants to tardigrades, lizards and larvaceans, Science News covered it all

tardigrade

I WILL SURVIVE  Scientists discovered some surprising biology among a diverse cadre of critters this year. Thanks to its impressive adaptations, one minuscule member, the tardigrade, may just outlive us all.    

3DSTOCK/SHUTTERSTOCK

2017 revealed some surprising biology of organisms large and small, from quick-dozing elephants to sex-changing lizards and carbon-dumping sea creatures.

bearded dragon
Bearded dragon lizards ARTHUR GEORGES/UNIV. OF CANBERRA
Switch it up

Toasty temperatures trump genetics when it comes to the sex of a bearded dragon lizard. Now researchers have found how RNA editing helps turn overheated male embryos into females (SN Online: 6/14/17).

larvacean
Giant larvaceans © 2017 MBARI
Homegrown

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).

sea spider
Antarctic sea spiders TIMOTHY DWYER (POLARTREC 2016), COURTESY OF ARCUS
Blood and guts

Antarctic-dwelling sea spiders 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).

fluorescent frog
Polka dot tree frogs C. TABOADA ET AL/PNAS 2017
Fluorescent fashion

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).

upside-down jellyfish
Upside-down jellyfish CALTECH
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.

African elephant
African elephants Bernard DUPONT/flickr (CC BY-SA 2.0)
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).

hydra
Hydra PROYECTO AGUA/FLICKR (CC BY-NC-SA 2.0)
Heads up

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
Flamingos CLINT/ISTOCKPHOTO
Balancing act

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.

tardigrade
Tardigrades K. ARAKAWA AND H. HIGASHIYAMA
Ultimate survivor

Tardigrades  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).

Blue chrysanthemum
Blue chrysanthemums N. NODA/NARO
Paint it blue

Scientists borrowed a gene each from Canterbury bells and butterfly peas to breed the world’s first true blue chrysanthemums. The method could be used to give other flower species the blues (SN: 8/19/17, p. 12).