Desperate times call for desperate measures. As food shortages hit, European earwig babies resort to eating each other’s faeces in their underground homes, helping to keep hunger and death at bay.
In times of plentiful food, the earwig offspring, or ‘nymphs’, feast on scraps of plant and insect material that their mother brings back from her trips above ground, and on food she regurgitates.
But when faced with limited supplies, the nymphs have to make do with what’s around them to survive.
Unlike many other insects that live in groups, European earwigs don’t clear their nest of faeces. Availability of faeces in hard times keeps the nymphs alive for about two more days on average than without them, researchers have now found.
In the lab, researchers deprived 56 five-day-old nymphs of food, and offered 28 of them faeces from their siblings. Nymphs with nothing to feed on survived for an average of 14 days, but those with access to their siblings’ faeces lived for an average of 16 days.
The metalmark butterfly cooperates with ants when it’s a caterpillar, only to stab them in the back when it has metamorphosed into a beautiful – thieving – butterfly.
While still a caterpillar, the metalmark butterfly wins over local ants, including those of the species Ectatomma tuberculatum, with gifts of sugary secretions. In return, the ants, which could easily eat the caterpillar or its adult butterfly form, defend the vulnerable caterpillars from other predators.
But this friendly give-and-take doesn’t last forever, work by Phillip Torres of Rice University in Houston, Texas and Aaron Pomerantz of the University of Florida, Gainesville, has now revealed. When the caterpillars have become butterflies, they turn on their protectors, plundering the source of their nectar.
This nectar is produced by organs called nectaries at the tips of new bamboo shoots, which are tended by ants. Using their mouthparts, they improve the flow from these nectaries, and stop them from running dry. The nectar is an important source of food for them, so they defend these nectaries fiercely.
These Indian dancing frogs are named for the antics males get up to when they want to grab the attention of a female.
Perched on a wet rock in a noisy, fast-flowing stream, a male sings and waves to the females. He lifts and stretches a leg to flag his white, webbed toe.
Any rival males on the territory are literally kicked out by the singing-and-dancing male.
It now turns out that this foot-waving, which was observed in nine species of the genus Micrixalus, is not the only bizarre trait that runs in the family. For the first time, researchers have found the tadpoles of a dancing frog, specifically the Kallar dancing frog (Micrixalus herrei).
Unlike most tadpoles, which live in water, they live underground until they develop into froglets.
One new genus and five new species of fan-throated lizards have been found in the drier parts of India.
Fan-throated lizards are small ground dwellers. The males flaunt a multihued, fan-shaped fold of skin on their throats during the breeding season.
Because they live in dry and barren soils, when the midday heat starts to get to them they skitter about on their rear legs. Fan-throated lizards are restricted to parts of South Asia. Little has been known about them since the first species was reported in 1829 from India. After this, only six more species have been found: three from Nepal, two from Sri Lanka and one from India.
Indian researchers, in collaboration with the Natural History Museum in London, have found a new species of burrowing, non-venomous snake that has smooth, shiny scales.
The species remained misidentified and stashed among museum specimens for a long time before scientists thought it might be distinct. To confirm their doubts, they looked in the wild – and unlike many museum finds that are extinct by the time they are discovered, this one still existed. And it continues to do so in the semi-evergreen forests of the Western Ghats of India.
The blue-capped cordon-bleu (Uraeginthus cyanocephalus) has a special talent. Not only can it sing, it can shake a leg or two. For its courtship display, it holds a piece of nesting material in its beak, points its head upward, moves up and down, and sings. Both males and females bob and sing like this, and choose their partner…
In a dry, open field in New Mexico, US, a hungry lizard spots a brightly-coloured, hairy insect scurrying across the sandy soil. Thinking it has found a meal, the lizard sprints to catch the insect. But once it has the insect in its mouth, it finds it is too hard to chew.
The lizard then moves the insect around to find a softer chewing angle but gets nowhere. Meanwhile the insect starts to squeak and finally stings the luckless lizard in its mouth. Alarmed, the lizard spits it out.
The insect, still squeaking, gets away unscathed. The lizard is left with nothing but a sore mouth and a foul taste.
This sturdy insect is a female velvet ant. These females have an arsenal of defences unmatched by their male partners, or any other insect. The question is, what terrifying predator forced the females to evolve so many defences? And if they are in such dire threat from predators, why are they brightly coloured?
A link between pupil shape and the feeding behaviour of animals has been made by studying the eyes of 214 species. By modelling how differently shaped pupils collect light, researchers in the UK and US have argued that the shape of an animal’s pupil – the aperture through which light enters the eye – is related to whether that animal is predator or prey.
The study reveals that herbivorous prey animals such as deer and zebras are likely to have horizontal pupils, while predators actively hunting during the day – like cheetahs and coyotes – usually have circular pupils. Furthermore, animals that hunt at night, or both day and night, tend to have vertical pupils. This vertical group includes some foxes, cats and snakes…
Study explains how wandering ants guide a group of food gatherers back to the nest.
When out of their nest, workers of the longhorn crazy ant (Paratrechina longicornis) band together toward a common goal: to bring food back to the nest. But even when a few of these long-legged, silver-haired ants (of Ant-Man fame) team up to carry a large item—such as a wasp—they often lose their way home.
Birds prepare their eggs for the worst, whether the risk comes from predators or just the location of their nests. This Easter I wrote about some of these amazing eggs for BBC Earth. Here’s one of the birds eggs I highlighted in my piece for their sheer camouflage (besides their beauty):
If her eggs have only a faint pattern, the female chooses a site that matches their colour. But if they have a strong pattern, she goes for a site that blends with it, and which hides the contour of the egg. This means the female must know the pattern of her own eggs.
To read about other wonderful bird eggs, click here!
A pair of phorid flies hovers over a wounded ant. While the male hangs back, the female lands and walks around the ant, examining it and poking it. Then she hops onto it and rips its head off. Finally, the female drags her trophy across the forest floor to an isolated, safe place, and eats it.
This never-before-seen behaviour is performed by an insect called Dohrniphora longirostrata. It belongs to a group of insects called phorid flies or scuttle flies, or sometimes “coffin flies”.
Several phorid flies have been nicknamed “ant-decapitating” flies because they, well, decapitate ants. But in every known case, the decapitation was incidental. For instance, fire ant decapitating flies lay eggs inside healthy fire ants. When the larvae hatch, they head straight for the ant’s head and feast on its contents. Eventually the head pops off the ant’s body, which is left behind twitching like a zombie.
D. longirostrata is the first phorid fly known to actively cut off an ant’s head before eating it. The discovery has been published in Biodiversity Data Journal.
An octopus’s arm is covered with hundreds of suckers that give it a strong tendency to attach to everything it encounters but the octopus’s arms. A team of researchers has shown that chemical signals from the skin of octopus protect its arms from attaching to each other or onto themselves, without which the octopus might end up entangled.
The team studied the behaviour of severed octopus arms — which remain active and move for at least an hour following separation — because arms have their own network of neurons that to some extent can work independent of the central control of brain.
Suckers on severed arms — like the ones on intact arms — attached to any surface but avoided the skin. They did attach to another arm but only at points where the skin was damaged or missing, suggesting that the skin, wherever present, might play a role in inhibiting the attachment.
Written by an ornithologist, Bird Sense is a fascinating account of the senses that enable birds to carry out their day-to-day activities like feeding or avoiding predators. Author Tim Birkhead, who has studied zebra finches and common guillemots for most of his scientific career, has successfully hinted at what it’s like to be a bird. Every chapter in the book deals with one sense—seeing, hearing, touch, taste, smell, magnetic sense and emotions—in birds as varied as owls and hummingbirds, making the science that goes into the discovery and understanding of the senses accessible to lay persons.
The book familiarises its readers with the amazing diversity of behavioural and anatomical adaptations that can be found in birds. A case in point is asymmetrical ears in some owl species that help owls locate the source of sound and find prey in the dark.
Bird Sense also informs its audience about the scientific process, suggesting how science builds on previous work. It talks about the debates and controversies some senses, such as those of smell and taste in birds, have sparked in the community of ornithologists. In author’s words, ‘For some inexplicable reason ornithologists have found it hard to accept that birds might have a sense of smell.’ Whether birds could have a sense of taste was debated for long, too. And even now, the idea of consciousness in birds remains controversial.