May 8, 2024

Sweet Irony: The Twisted Behavior of Starving Argentine Ants

Argentine ants have actually been able to displace native ant species in large part because of their aggressive foraging for sugar and other carbs.
Nevertheless, when theyve been denied of food and rivals exist, they considerably restrict their foraging activity instead of vigorously pursuing food.
On the whole, this technique may provide a benefit to their colonies, researchers say.

Their findings, released in the journal Current Zoology, suggest that the aversion of Argentine ants to expose themselves to danger when weakened by appetite could perhaps provide an one-upmanship over other species by assisting to preserve their colonies foraging abilities.
” While not foraging might lead to a reduction in food shops when those shops are currently low, foraging in a high-risk environment exposes the nest to potential loss of foragers,” said the research studys senior author, Noa Pinter-Wollman, a UCLA professor of ecology and evolutionary biology. “So reduced foraging could be analyzed as specific foragers not taking unneeded risks.”
Ant colonies adjust their foraging strategies according to the accessibility of these food sources, the existence of competing ant species, and the hazard of predators or other dangers. Well-fed ants will forage for carbs even in the presence of other ant types or threat cues.
Author Bryce Barbee, who carried out the research as a UCLA undergrad, expected that starving Argentine ants of either carbs or protein would just increase their desire to forage for those foods in high-risk environments due to the fact that they had little to lose and everything to gain.
Together with Pinter-Wollman, Barbee created a series of lab experiments that involved feeding ants usually, denying them of either carbohydrates or protein, and denying them of both, then permitting them to forage as they usually would in either low-risk or high-risk environments.
The researchers created the impression of high-risk environments with formic acid, a chemical marker produced by ants, to signal the presence of competitors.
When the threat was low, starving ants did certainly forage more vigorously for the food of which they had been deprived. When the threat was high, starving ants shocked the scientists by ending up being more careful, not less, in their foraging strategies.
In both high- and low-risk foraging circumstances, the ants were more ready to forage for carbohydrates than protein, which they just need to raise their brood. Considering that no eggs or pupae existed in the laboratory nests, this finding might not be unexpected, but it might likewise indicate that starving ants put their own energetic needs ahead of raising offspring, the researchers stated.
Scientists who study animal habits have advanced 2 ideas to discuss foraging strategies. The first, understood as the asset-protection principle, holds that hungry animals have less to lose than satiated animals and will for that reason act more assertively to get food. The second, the state-dependent safety hypothesis, holds that animals in great condition are more likely to take threats since they are more most likely to endure threats they encounter.
” Our work promoted the state-dependent security hypothesis however not the asset-protection concept,” stated Barbee, now a doctoral trainee at UC Santa Barbara. “The findings recommend that aspects such as activity level and energetic expenses of starvation are necessary for Argentine ant foraging decisions.”
The work points towards an avenue of research that could lead to much better efforts to control the spread of Argentine ants and reduce their detrimental impact on farming, the scientists said.
Reference:” Nutritional needs and death danger integrate to shape foraging choices in ants” by Bryce Barbee and Noa Pinter-Wollman, 12 November 2022, Current Zoology.DOI: 10.1093/ cz/zoac089.

To support the energetic requirements of everyday life, all ants require carbs, which they acquire from a range of plant and animal sources. Ant colonies adjust their foraging strategies according to the accessibility of these food sources, the presence of contending ant types, and the threat of predators or other risks. Well-fed ants will forage for carbs even in the existence of other ant types or risk cues.
Scientists who study animal behavior have advanced 2 ideas to describe foraging strategies. The first, understood as the asset-protection concept, holds that hungry animals have less to lose than satiated animals and will therefore behave more assertively to get food.

An Argentine ant tending aphids, plant parasites that secrete a sugar-rich compound the ants consume. Credit: UCLA/Noa Pinter-Wollman
In a twist that surprised UCLA researchers, starving ants were more cautious, not less, in their search for food.

It may appear like typical sense that a starving animal is most likely to take dangerous threats to get food than one with a full belly. But brand-new research study from the University of California, Los Angeles (UCLA) reveals that groups of Argentine ants, who forage boldly when theyre well fed, exercise much more care when theyve been deprived of carbs and the dangers from competitors are high.
This counterintuitive foraging technique might contribute to the success of these insects, referred to as Linepithema humile, an invasive species that displaces native ant populations in California and somewhere else and has become a considerable agricultural insect, the researchers said.