Hungry caterpillars, COVID-19 and wildlife and more in current eco-news

Very hungry, angry caterpillars

Monarch butterflies are famously archetypal of their species. Their preferred food is milkweed and researchers wanted to see what happens when food is scarce for monarch caterpillars. At their hungriest, a monarch caterpillar can consume a milkweed leaf in five minutes. The researchers built an open milkweed garden that they grew without chemical additives that might confound the experiment. They then took monarch caterpillars that naturally grew on the milkweed into the lab and placed them in groups with different amounts of milkweed. They found that the less food was available, the more likely caterpillars were to headbutt each other out of the way and generally be more aggressive. The tentacles that the caterpillars use to sense the physical world around them were not active during the fights, so it was pheromones or some other mechanism that was promoting the aggression. Whatever the motivation though, those very hungry caterpillars were also very angry.

Source: iScience

COVID-19 and the wildlife trade

In a new report, researchers from the University of Göttingen have observed that the COVID-19 pandemic has focused attention on preventing the next outbreak, and for that to happen humanity’s relationship with the natural world must change. They say that there needs to be urgent action to regulate the trade of wildlife and reduce demand for wildlife parts and products. Already, the governments of China, Vietnam and Korea have introduced some form of regulation to control wildlife trade since the outbreak. However, the researchers warn against a sudden blanket ban on all wildlife products, as this will have a disproportionately high negative impact on disadvantaged, migrant and rural populations that depend on such markets for their subsistence. They recommend that governments work with local communities to create and maintain alternative means of subsistence before bans on live animals and non-food wildlife products are implemented.

Source: Trends in Ecology and Evolution

Glyphosate and the microbiome

Bioinformatics is a research discipline that combines biology and computer science to store and analyse biological data. In a new study, researchers used bioinformatics to assess the sensitivity of organisms to glyphosate, the most commonly used broad-spectrum herbicide. Glyphosate targets and enzyme called EPSPS synthase in the shikimate pathway. Since this pathway only exists in plants, fungi and bacteria, glyphosate is considered safe. In this bioinformatic analysis, however, researchers found that 54 per cent of human core gut bacterial species are potentially sensitive to glyphosate. Disruptions to the human gut microbiome are known to impact your mental health, heart health, immunity and much more. Home gardeners need to be aware of this and we need to be mindful of it when it comes to our food chain. The researchers say that even low glyphosate residues may have some impact on our all-important microbiome.

Source: Journal of Hazardous Materials

Pesticide in honey

Researchers have developed an environmentally friendly method of extracting substances called pyrethroids from honey. Pyrethroids cause paralysis and death in insects, and are one of two major groups of pesticides that contribute to colony collapse disorder in bees. In this disturbing phenomenon worker honeybees just disappear, leaving the queen and other members of the hive to die. In the course of producing honey, bees pollinate billions of dollars’ worth of crops worldwide. Being able to extract pyrethroids from honey makes it easier to measure whether the honey is safe for human consumption, but also help identify in what areas farmers use pyrethroids and in what amounts. The hope is that measuring pyrethroids in honey will allow tracking where these pesticides are in use at unsafe levels, with a view to ultimately modifying agricultural practice in order to help protect the honeybee population. Of the honey tested in this study, all contained pesticides at allowable levels.

Source: Food Chemistry