Bees seem to show when they are pleased and like something, rather than just needing it, in one of the strongest signs yet that insects have subjective experiences.

In recent decades, it has become clear that bees are capable of more complex behaviours than we previously thought, such as counting and demonstrating a sense of rhythm. But discerning whether they have inner states akin to our emotions is more difficult. For one thing, insects don’t have the flexible facial musculature of mammals, which we use to communicate our feelings.

“How can we get any behavioural readout of these insects with a hard body and their mask of a face,” asks at Macquarie University in Sydney, Australia. “Do bees have any sort of inner state whatsoever?”

To solve the mystery, Barron and his colleagues ran a series of experiments involving buff-tailed bumblebees (Bombus terrestris).

First, the team offered the bees a water droplet containing sugar, along with others that contained salt and quinine, while filming them using high-resolution video.

After tasting the sweet liquid, the bees repeatedly stuck out their glossa, which is a hairy tongue that they use to lap up nectar in flowers. After tasting the salty and bitter samples, the bees wiped their mouths and shook their heads.

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However, both responses may have just been a reaction to the different chemicals, rather than a sign of enjoyment or displeasure, says Barron.

Next, the researchers reduced the concentration of the sugar and mixed it with a small amount of salt, resulting in a dramatic reduction of the glossa protrusions. Then they exposed the bees to 40°C (104°F) temperatures to dehydrate them, after which, when the bees were offered salty droplets, the bees repeatedly protruded their glossa.

“If I just handed you an electrolyte drink right now, you’d probably think, ‘well, that actually tastes pretty foul’,” says Barron. “But if you had just come back from a long run and I handed you an electrolyte drink, you’d think, ‘that’s fantastic’. It’s because your internal state has changed, and that internal state is changing your evaluation of things – that’s what we think we’re seeing in the bees.”

For the final part of their experiment, the researchers wanted to determine what would happen if they meddled with the chemistry that, in mammals, underpins appetite and the enjoyment of food.

When the bumblebees were treated with dopamine, which in mammals affects the motivation to seek food, their glossa protrusions didn’t increase, suggesting that although they had greater desire, their enjoyment “tell” – tongue protrusions – didn’t change.

But when the bees were treated with endocannabinoids, which increases the “liking” of food in mammals, it led to an increase in their glossa protrusions.

“What this is showing us is that even from an animal like a bee, there is some sort of inner life for that insect,” says Barron. “There’s something going on. It’s evaluating its world. It’s experiencing its world and it’s not a robotic entity running on a program.”

at the California Institute of Technology says the research is “an important and innovative study on a difficult topic”. “The evidence presented in the paper shows that the bees represent the value of the taste stimuli in a flexible manner,” he says. But it is unclear whether the experiments demonstrate pleasure as we know it.

“The idea that facial expressions are literally constitutive of emotions is clearly not the case. Actors can fake them, and people whose faces are paralysed still have emotions,” he says. “I think we should conclude that bees have bee emotions, not mammal emotions.”

at the London School of Economics says the study is the first time he has  seen “wanting” and “liking” disentangled in a bee.

“We underestimate insects so much,” he says. “It’s led to a golden age of very charming studies where scientists use modern techniques – sometimes just high-resolution, high-frame-rate video, as in this study – to reveal behaviours people have been missing.”

A parasitic species of ant from Japan is the first ever found to have done away with both males and female workers – instead, every individual is a queen that tries to take over the nests of other species.

Typically, ant colonies consist of a queen, female workers and short-lived males that die after mating.

For more than 40 years, researchers have suspected that the rare parasitic ant Temnothorax kinomurai only produces queens, but until now there has been no definitive proof.

Young queens of this parasitic species take over the nests of a related species, Temnothorax makora, killing the host queen and some workers by stinging them. They then reproduce asexually, producing cloned offspring in a process called parthenogenesis, which is rare in ants but common among some other insects. The T. makora workers are duped into helping raise the young T. kinomurai queens.

at the University of Regensburg, Germany, and his colleagues collected six colonies with T. kinomurai queens and reared them in artificial nest boxes in the lab. From these colonies, they were able to breed and raise 43 queen offspring in the lab. Inspection of their genitalia confirmed that there were no males.

These 43 queens were then given the opportunity to take over colonies of T. makora. Seven queens survived and succeeded in their coup attempts. They produced another 57 offspring, which were again confirmed to be all female queens.

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“They exhibit an entirely new form of social organisation, adding another exciting dimension to the already rich and varied world of ants,” says Heinze.

Invading colonies of other species is a risky strategy, as shown by the high failure rate of queens seen in this study. But if all your offspring are queens, you have more chances to start new reproductive colonies.

“If parthenogenesis evolves due to random mutation, as in T. kinomurai, queens can produce 100 daughters, which do not need to mate – hence, there are 100 queens that try to found a new colony,” says Heinze. “Obviously, the success of parthenogenetic queens is higher than that of sexual queens.

“This species may be considered the final step in the evolution of social parasitism, highlighting the enormous flexibility in the life histories of social insects,” he says.

A severed mosquito proboscis can be turned into an extremely fine nozzle for 3D printing, and this could help create replacement tissues and organs for transplants.

at McGill University in Montreal, Canada, and his colleagues developed the technique, which they call 3D necroprinting, because they were unable to find nozzles thin enough for their work on manufacturing very fine structures. The narrowest commercially available nozzle they could find had an interior bore of 35 micrometres and also came with a hefty £60 ($80) price tag.

They experimented with techniques like glass-pulling, but found these nozzles also proved expensive and were very brittle.

“This made us think whether there is an alternative,” says Cao. “If Mother Nature can provide what we need with an affordable cost, why make it ourselves?”

The researchers tasked a graduate student, , with finding a natural organ that could handle the task, considering everything from scorpion stingers to snake fangs. They eventually found that a mosquito proboscis – in particular, the stiffer version found in female Egyptian mosquitoes (Aedes aegypti) – allowed them to print structures as thin as 20 micrometres.

Cao says an experienced worker can make six nozzles an hour from mosquito mouthparts at a cost of less than a dollar each, making the process easy to scale up. The natural nozzles can be fitted to existing 3D printers and are relatively long-lasting considering their biological origin: after two weeks, around 30 per cent of them begin to fail, but they can be stored frozen for up to a year.

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The team tested the technique using a bio-ink called Pluronic F-127, which can build scaffolds for biological tissues including blood vessels – a potential method for creating replacement organs.

There have been several other examples of parts from small creatures being used in machines, including a moth antenna used in a smell-seeking drone and

at Swansea University, UK, says the work is another example of human engineers struggling to match the tools developed by nature.

“You’ve got a couple of million years of mosquito evolution: we’re trying to catch up with that,” he says. “I think that maybe they’ve got the advantage on us there.”

An array of perfectly preserved insects and even a spider’s web, encased in 112-million-year-old amber, have been found in a quarry in the Amazon rainforest.

 at the University of Barcelona, Spain, and his colleagues had heard that amber – fossilised tree resin – had been recovered from the Genoveva quarry, in the Oriente basin of eastern Ecuador, and headed there in 2022 to see for themselves.

The amber at the site is thought to come from the resin of conifers in the Araucaria family, which covered the region when modern-day Ecuador was part of the Gondwana supercontinent.

Amber deposits come from two main sources: the above-ground parts of trees and the roots. Those from above the ground sometimes preserve the remains of insects and other life forms that got stuck in the resin that then turned to amber. These preserved remains are known as bio-inclusions.

Most of the amber found at the quarry was formed from sources below the ground, but during a preliminary dig at the site, the team collected 60 promising chunks of above-ground amber that were brought back to the lab for preparation and study.

More than a third of these contained bio-inclusions such as insects, plant parts and even a spider’s web that date to the Cretaceous Period, which is part of the Mosazoic Era. “This is the first time that [Mesozoic] amber with bio-inclusions of insects and spiders has been found in all of South America and they are certainly new species,” says Delclòs.

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The insects included many different kinds of flies as well as wasps, midges, a beetle and mosquitoes, all of which lived alongside dinosaurs in a humid forest close to the equator. Some of the species are dependent on water to complete their life cycles, so lakes, rivers and swamps were probably plentiful.

If a person was to visit the site at that time, says Delclòs, they would definitely need insect repellent. “And probably also some way of escaping from a carnivorous dinosaur or two,” he says.

“There are several mosquitoes that would be blood-feeding and this would indicate that at some point in their life cycle they would need the blood of vertebrates, possibly avian or non-avian dinosaurs.”

However, any dinosaur DNA that may have once been in the blood consumed by the mosquitoes presevered in the amber would have been destroyed long ago, most likely by chemicals in the resins. “We cannot have a Jurassic Park from Cretaceous amber, at least with current techniques,” says Delclòs.

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