Ants and dead dragonfly


This 20 June 2017 video is about a dragonfly killed by a cat. After its death, the dragonfly attracted many ants.

Eight-year-old Gianni from the Netherlands made this video.

Ants transport dead caterpillar


In this 30 May 2017 video from the Netherlands, ants find a dead caterpillar. With some difficulty, they transport it to their nest.

Injured African ants brought back to nest to recover


This video says about itself:

No Ant Left Behind: Warrior Ants Carry Injured Comrades Home

12 April 2017

Leave no man behind. That’s an old idea in warfare — it’s even part of the Soldier’s Creed that Army recruits learn in basic training.

And never leaving a fallen comrade is also the rule for some warriors who are ants, according to a report published Wednesday in the journal Science Advances.

These ants, Megaponera analis, hunt and eat termites. Scouts will go out, find a group of termites, and then return to the ant nest to muster the troops.

Biologist Erik Frank explains that 200 to 500 ants will march out in formation. “Like three ants next to each other, in a 2-meter-long column,” he says. “It’s very peculiar and it looks like a long snake walking on the ground.”

When the termites spot this invading army, they try to escape, but the fighting is fierce.

“And after roughly 20 minutes the battle is over,” says Frank, a doctoral student with the University of Würzburg in Germany who is researching animal behavior and evolution. “You have a lot of termites lying dead on the ground,” he says, “and the ants start collecting the termites to return.”

A few years ago, Frank was working at a field station in the Ivory Coast when he noticed that some of the ants marching home after battle weren’t carrying termites. Instead, they were carrying other ants.

“And I was wondering, ‘What exactly was going on there? Why were they carrying some of the ants?'” he recalls.

It turns out, those transported ants weren’t dead — they were injured.

Ants sometimes lose a leg or two, which makes it hard for them to walk. Or, they can be weighed down by a dead termite whose jaws had clamped onto them. Either way, they’re slower than uninjured, unburdened ants.

By marking these injured ants with paint, Frank learned that in nearly all cases, they made a full recovery after being carried home to recuperate. They learn to walk with fewer legs, and their ant buddies apparently will pull off stuck termites. It doesn’t take long for an ant that’s been hurt to once again be ready for action.

Credit: Frank et al./Science Advances

“We saw them again, participating in hunts the next day,” says Frank.

He and his colleagues did some experiments to see what would happen to injured ants that weren’t carried home. It turns out that these poor ants couldn’t march fast enough. So they fell behind — and frequently got eaten by spiders and other predators, the researchers report.

From Science Advances:

Saving the injured: Rescue behavior in the termite-hunting ant Megaponera analis

Erik Thomas Frank, Thomas Schmitt, Thomas Hovestadt, Oliver Mitesser, Jonas Stiegler and Karl Eduard Linsenmair

12 April 2017

Abstract

Predators of highly defensive prey likely develop cost-reducing adaptations. The ant Megaponera analis is a specialized termite predator, solely raiding termites of the subfamily Macrotermitinae (in this study, mostly colonies of Pseudocanthotermes sp.) at their foraging sites.

The evolutionary arms race between termites and ants led to various defensive mechanisms in termites (for example, a caste specialized in fighting predators). Because M. analis incurs high injury/mortality risks when preying on termites, some risk-mitigating adaptations seem likely to have evolved.

We show that a unique rescue behavior in M. analis, consisting of injured nestmates being carried back to the nest, reduces combat mortality. After a fight, injured ants are carried back by their nestmates; these ants have usually lost an extremity or have termites clinging to them and are able to recover within the nest.

Injured ants that are forced experimentally to return without help, die in 32% of the cases. Behavioral experiments show that two compounds, dimethyl disulfide and dimethyl trisulfide, present in the mandibular gland reservoirs, trigger the rescue behavior.

A model accounting for this rescue behavior identifies the drivers favoring its evolution and estimates that rescuing enables maintenance of a 28.7% larger colony size. Our results are the first to explore experimentally the adaptive value of this form of rescue behavior focused on injured nestmates in social insects and help us to identify evolutionary drivers responsible for this type of behavior to evolve in animals.

Megaponera analis lives in Africa.

Rare ant, first time on Texel island


Temnothorax albipennis, photo © 2017 California Academy of Sciences

This photo, by the California Academy of Sciences, shows a Temnothorax albipennis ant.

This species is rare in the Netherlands. It lives only in the west coast sand dunes, from Voorne to the Zwanenwater nature reserve.

Warden Erik van der Spek reports today that he found a Temnothorax albipennis ant in the Westerduinen sand dunes of Texel last summer. This is a first for the island, and also a first for anywhere north of Zwanenwater. It was a winged female.

Fijian ants as agriculturists


This video says about itself:

27 November 2016

Scientists on the island of Fiji have discovered a type of ant that plants, fertilizes & guards its own coffee crops. The ant, known as “Phildris nagasau” has been perfecting this practice for millions of years. The ants reportedly don’t just harvest the nectar from the plants, they also use the coffee plants as a place to live. According to the scientists, this is the first ant to build its own home. In an experiment, researchers discovered that the ants plant six different types of coffee plant in the bark of jungle trees.

From Nature:

Obligate plant farming by a specialized ant

Guillaume Chomicki & Susanne S. Renner

21 November 2016

Abstract

Many epiphytic plants have associated with ants to gain nutrients. Here, we report a novel type of ant–plant symbiosis in Fiji where one ant species actively and exclusively plants the seeds and fertilizes the seedlings of six species of Squamellaria (Rubiaceae). Comparison with related facultative ant plants suggests that such farming plays a key role in mutualism stability by mitigating the critical re-establishment step.

Rarely-seen event of ant brood parasitism by scuttle flies video-documented: here.

Blackbird uses ants against parasites


In this 17 November 2016 video, a blackbird uses ants and their formic acid against parasites.

Harry ten Veen in the Netherlands made this video.

Ants cooperating to get piece of bread into their nest


This 6 June 2016 video shows ants cooperating to get a (for ants) big piece of bread through the narrow entrance of their colony.

The video is by mmjiskoot in the Netherlands.