In the Olympic Games of Ancient Greece, long-jumpers would leap while carrying weights called halteres in their hands. From either a standing start or a short run, they swung the weights and leapt as their arms came forward. The halteres each weighed up to nine kilograms, and would have added around 17 centimetres to a 3 metre jump. Olympians first used the hand weights in 708 BC, but other apes were jumping with a very similar technique millions of years earlier – gibbons.

Gibbons are undisputed masters of the treetops, best known for swinging around at unfeasible speeds from their long, powerful arms. Their wrists contain ball-and-socket joints, which allow their entire body to easily pivot about their hands. This style of movement, known as brachiation, is a gibbon speciality (see video below). But these apes are also accomplished jumpers. Field scientists have watched them clear gaps as large as 10 metres.

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The flying lemur must be one of the most inaccurately named animals in the world, for it cannot fly and it isn’t a lemur. This is why most biologists prefer to refer to it by its other name – the colugo. It lives in the forests of South-East Asia, where it glides (not flies) from tree to tree. From a standing start, it launches itself into the air with a powerful jump and spreads the massive membrane that runs from its chin to its hands, feet and tail.

The glide looks effortless, but Greg Byrnes from the University of California, Berkeley has found that it’s a surprisingly inefficient means of travel. Contrary to expectations, gliding actually takes up more energy than travelling the same distance by running and jumping through the canopy. So why do it? Byrnes has the answer – it saves time. For the busy modern colugo, gliding saves precious minutes that could be better spent on eating, mating or whatever it is that colugos do.

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Somewhere on the side of your thigh bone, there is a tiny hole. It’s called a “nutrient foramen”. An artery passes through this gap, suffusing the bone with blood and oxygen. The hole is found in all thigh bones, from those of birds to lizards, and it always fulfils the same function. But it can also double as a keyhole into the past, allowing us to peek at the lives of animals long extinct.

Roger Seymour from the University of Adelaide has used the size of these holes to show that many dinosaurs of all sizes led active lifestyles.

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The wings of bats provide them with support and lift as they fly. But they are also giant sensors that tell bats about the flow of air around their bodies, helping them to execute sharp manoeuvres without crashing.

The wings’ ability to monitor airflow depends on tiny hairs that cover their surfaces. The hairs were discovered almost a century ago. Scientists suggested that they are sense organs that allow bats to fly in complete darkness. That idea fell out of favour in the 1940s when Donald Griffin and Robert Galambos showed that bats navigate by listening for the echoes of their own calls. The discovery of bat sonar solved the mystery of their night-time aerobatics, and the wing hairs fell into obscurity.

But John Zook at Ohio University had not forgotten about them. He has shown that the pre-sonar theories were partly correct. The hairs complement a bat’s echolocation and turn it into a better flier, allowing the animal to “feel” its way through the sky.

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The competition between cats and dogs often takes amusing turns. Last year, cats seemed to edge ahead in the ‘drinking’ event. Until recently, people thought that both pets drink by using their tongues as simple ladles to lap up liquids. But Pedro Reis and Roman Stocker from MIT found that cats do something very different. Using high-speed video recordings, they showed cats drink by using their tongues to draw columns of water into their open jaws. While dogs supposedly drink by scooping up water in a mundane way, cats were portrayed as masters of physics that “defeat gravity” whenever they drink.

Now, A. W. Crompton and Catherine Musinsky from Harvard University have stepped up to even the score for dogs. Through their own high-speed videos – including X-ray films of drinking dogs – they have found that dogs use the same technique the cats do. It’s a draw.

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This animal is not an earthworm. It is long and sinuous, it lives underground, and its flanks look like they’re lined with rings. But it is not an earthworm – after all, it has a skeleton, jaws, scales, and two stubby legs. It is a “worm lizard” or amphisbaenian.

Amphisbaenians are a group of burrowing lizards, and one of the most mysterious groups of reptiles. They’re named after Amphisbaena, a Greek serpent with a second head on its tail – indeed, amphisbaeneans do have tails that look a bit like their heads. They are meat-eaters, and they search for their prey underground, burrowing through the soil with strong, reinforced skulls. Most species are completely legless, but four of them – the ajolotes (including the one in the photo above) – have bizarre, stunted arms.

Their origins are mysterious. Their bones suggest that they are close relatives of snakes and obviously, neither group has any legs. But their genes tell a different story – they say that the amphisbaenians are most closely related to the lacertids, a common group of lizards. Now, Johannes Muller from Berlin’s Natural History Museum has found a fossil lizard whose features might settle the debate in favour of the lacertid camp.

Muller named his animal Cryptolacerta hassiaca, which means “hidden lizard from Hesse”. He found it in the Messel Pit, a disused quarry near the town of Hesse. The quarry has no shortage of famous former residents, including the over-hyped Darwinius, the giant bird Gastornis, and leaves that were scarred by fungus-infected ants. Cryptolacerta is the latest addition to this treasure trove of famous fossils

Muller used a CT scanner to get a glimpse of Cryptolacerta’s body, which was fully preserved except for the tip of its tail. Its huge skull has many features that are characteristic of amphisbaenians, including small eye sockets, indicating tiny eyes, and heavy thickened bone, making it strong and inflexible. That’s a far cry from the light, bendy skulls of snakes. Its body, however, looks far more lizard-like – it obviously has four legs, albeit small ones.

Muller compared Cryptolacerta’s features with those of other modern reptiles, and produced a family tree that linked them together. Cryptolacerta itself sat at the base of the amphisbaenean branch – it was an early member of the group. Meanwhile, the amphisbaenians and lacertids sat on adjacent branches, far away from the snakes.

This supports the genetic view: amphisbaenians are closely related to lacertids, and their superficial similarity to snakes is a great example of convergent evolution. They both evolved long legless bodies in independent ways.

With its legs and squat body, Cryptolacerta clearly wasn’t the specialist burrower that the amphisbaenians have become. By comparing its shape to other lizards, Muller thinks that it spent its days hidden among the leaf litter, burrowing from time to time when the opportunity arose. This concealed lifestyle may have been an intermediate step between open-air scurrying and fulltime burrowing.

Many burrowing animals, from worms to legless lizards (and there are at least 8 groups of those), have long bodies and no limbs, so it’s tempting to think that these features are a prerequisite for an underground life. But Cryptolacerta, with its reinforced skull, tells a different story – it suggests that early amphisbaenians adapted to a digging lifestyle headfirst. Only after they thickened their skulls did they lose their legs and lengthen their body.

Reference: Muller, Hipsley, Head, Kardjilov, Hilger, Wuttke & Reisz. 2011. Eocene lizard from Germany reveals amphisbaenian origins. Nature http://dx.doi.org/10.1038/nature09919

Image by Gary Navis and Robert Reisz

More on lizards:

• Mayfly-like chameleon lives mostly as an egg
• Lizard claws shed light on the evolutionary origin of hair
• The pink Galapagos iguana that Darwin never saw
• Venomous Komodo dragons kill prey with wound-and-poison tactics
• Three desert lizards evolve white skins through different mutations to the same gene

If Spider-Man really could do “whatever a spider can”, he ought to shoot webs from somewhere less salubrious than his hands. All spiders spin silk from their rear ends, using special organs called spinnerets. But one group – the tarantulas – can also shoot silk from their feet, and they use this ability to climb up sheer vertical surfaces.

Tarantulas have been kept as pets for decades, but their silk-spinning feet were only discovered in 2006 by Stanislav Gorb from the Max Planck Institute. Gorb watched Costa Rican zebra tarantulas climbing up glass plates, and saw that they left behind silken footprints – dozens of fibres, just a thousandth of a millimetre wide.

As the spider climbs, four of its legs leave the glass plate at any one time. As the legs land, they begin to slip but small nozzles secrete a viscous silken fluid that rapidly hardens and adheres to the surface. The silk acts as a tether, firmly holding the spider to the pane.

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The southern beaches of Cumberland Island, off the coast of Georgia, USA, are part of a national park. To protect the area, only residents and staff are allowed to drive their vehicles on the sands. But there are plenty of wheels nonetheless – small, living ones.

The beaches are home to the beautiful coastal tiger beetle (Cicindela dorsalis media). Tiger beetles are among the fastest of insect runners, but their larvae are slow and worm-like. If they’re exposed and threatened, running isn’t an option. Instead, they turn themselves into living wheels. They leap into the air, coil their bodies into a loop, and hit the ground spinning. The wind carries them to safety.

The fact that a long, worm-like animal can jump and roll is amazing in its own right. The ability is even more remarkable because the tiger beetle is “one of the best-studied insect species in North America” and until a few years ago, no one had ever seen it doing this. Alan Harvey and Sarah Zukoff were the first. They write, “[Sarah] was walking through some unusually loose sandy drifts on Cumberland Island and happened to kick up some C. d. media larvae, which promptly started wheeling.”

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In 1996, a loggerhead turtle called Adelita swam across 9,000 miles from Mexico to Japan, crossing the entire Pacific on her way. Wallace J. Nichols tracked this epic journey with a satellite tag. But Adelita herself had no such technology at her disposal. How did she steer a route across two oceans to find her destination?

Nathan Putman has the answer. By testing hatchling turtles in a special tank, he has found that they can use the Earth’s magnetic field as their own Global Positioning System (GPS). By sensing the field, they can work out both their latitude and longitude and head in the right direction.

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In the wild, you may occasionally see a penguin wearing a metal band around the base of one of its flippers. These bands aren’t the latest in penguin bling – they’re tools used by scientists to track the lives and movements of individuals. The bands are controversial – some say that they are innocuous, while others argue that they slow and hurt the very birds that scientist are trying to conserve. Now, Claire Saraux from the University of Strasbourg has evidence that might swing  the debate – a ten-year study showing that banded birds die sooner and raise fewer chicks.

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