Octopoteuthis rugosa

A new study led by the <a href="https://www.uc.edu/">University of Cincinnati</a> has found that nighttime <a href="https://www.earth.com/news/light-pollution-has-increased-almost-everywhere/">light pollution</a> can interfere with the extraordinary navigational abilities of monarch butterflies, which often travel from Canada to Mexico during multigenerational migrations. Since artificial nightlights interfere with butterflies’ circadian rhythms, the animals often become disoriented and fly when they should be resting.



Scientists have long known that light pollution can significantly disrupt normal circadian rhythms and sleep-wake cycles of both wildlife and humans. For instance, previous studies have shown that city lights interfere with the navigation of animals such as baby sea turtles, which mistake the artificial lights for the glow of the moon on the ocean, and head out of the water when they should in fact be hatching.&nbsp;



While researchers have already investigated in great depth the effects of light pollution on birds and other animals that migrate at night, animals that migrate during the day, such as the monarch butterflies, have received far less attention.



Although the erratic, circuitous movements taking them to and fro across gardens or orchards can make it difficult to imagine that these creatures are able to stick to a rigid flight plan, their mass migrations across entire continents is a clear proof that they have remarkable navigational capacities.&nbsp;



For instance, millions of monarch butterflies living east of the Rocky Mountains leave their summer breeding grounds in southern Canada and northern US, and travel as much as 4,000 kilometers to overwintering sites across Mexico. They can take up to five generations during this cross-continent journey, which is made possible by amazingly precise internal clocks that tell them where to orient themselves in relation to the position of the sun.



Yet, researchers have now found that monarchs exposed to nighttime light pollution – such as street lamps above their tree roosts – can experience a phase shift, making their bodies think that it’s either earlier or later than it really is. “It’s like jet lag,” said study senior author Patrick Guerra, an assistant professor of Biology at the University of Cincinnati. “Essentially, their sense of time is disturbed.”&nbsp;



By conducting controlled laboratory experiments that simulated and isolated the effects of light trespass perturbation on the monarchs, Professor Guerra and his team found clear evidence that light pollution disrupts the animals’ day-night cycle. Thus, if we want to be hospitable to these beautiful creatures, we should protect them from exposure to nightlights. “It’s something to think about if you’re making a pollinator garden or if you want to be eco-friendly,” Guerra&nbsp;advised.



The study is published in the journal <a href="http://dx.doi.org/10.1016/j.isci.2022.104310">iScience</a>.&nbsp;&nbsp;&nbsp;&nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Light pollution disorients monarch butterflies

A new study led by the University of Cincinnati has...

Pterosaur,Scene,3d,Illustration

With gigantic wings that reach 10 meters in length, the Quetzalcoatlus was the largest flying species to have ever lived. One of the most exciting moments of the new Jurassic Park sequel, Jurassic World Dominion, is when one of these giant <a href="https://www.earth.com/news/mystery-solved-pterosaurs-had-colorful-feathers/">pterosaurs</a> swoops down and attacks the heroes’ aircraft.&nbsp;



However, researchers from <a href="https://en.nagoya-u.ac.jp/">Nagoya University</a> suggest that the movie gets it wrong. By undertaking aerodynamic analysis, the experts have demonstrated that Quetzalcoatlus would not have been able to fly more than a short distance.&nbsp;



The research team compared the ability of extinct giant flying creatures and modern birds to soar using wind and air currents in an energy-efficient way..



There are two types of soaring: thermal soaring, which uses updrafts to ascend and glide, such as eagles and frigatebirds; and dynamic soaring, which uses wind gradients over the ocean, as in the case of albatrosses and petrels.&nbsp;



The performance of thermal and dynamic soaring was calculated for four extinct species and compared to the performance of present-day birds. The research team found that the famous Pteranodon of Jurassic Park III fame likely excelled at soaring using updrafts over the sea, similar to modern frigatebirds.



However, the study found that Quetzalcoatlus was not suited for soaring flight even when atmospheric density parameters were changed. This was largely due to the proportions of its large wings and large body size resulting in poor performance.



“This suggests that the wind conditions under which Quetzalcoatlus could conduct sustainable thermal soaring were limited," explained the study authors&nbsp; Although it had previously been thought that Quetzalcoatlus was a proficient thermal soarer able to cover 10,000 miles without touching the ground, our studies show that its thermal soaring abilities were below that of modern birds."&nbsp;



"We suppose that&nbsp; the flight styles of Quetzalcoatlus and other similar sized pterosaurs were similar to those of the kori bustard that is a short-range flyer and spend most of their time on land.”&nbsp;



The experts also looked at two extinct giant birds, Argentavis magnificens, the heaviest flying bird that ever existed, and Pelagornis sandersi, which had the largest known wingspan. Here, a surprising discovery was found. Like previous studies which showed that Argentavis was suited to thermal soaring, the results of the current study found that Pelagornis was suited to thermal soaring, (despite previous studies that thought the bird used dynamic soaring).



While these findings were released too late to improve Jurassic World Dominion, the results will likely change the way extinct giant birds and pterosaurs are portrayed in future sequels.



The study is published in the journal <a href="https://academic.oup.com/pnasnexus">PNAS Nexus</a>.



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Jurassic Park was wrong about how fast pterosaurs could fly

With gigantic wings that reach 10 meters in length, the...

A new strategy using technology like satellites and <a href="https://www.earth.com/news/drones-can-help-monitor-the-health-of-remote-seabird-colonies/">drones</a> can provide key information to protect pollinators. The researchers examined innovative ways of using these techniques to track the availability of flowers. When combined with behavioral studies, this could help us see the world through the eyes of insects.



The flowers that are available to insects can vary, and human activities are changing landscapes in ways that affect pollinators. The University of Exeter researchers hope their findings can help better understand these changes, leading to better conservation.



"Recent advances in drone and satellite technology have created new opportunities," said lead author Dunia Gonzales, from the <a href="https://psychology.exeter.ac.uk/research/centres/crab/">Centre for Research in Animal Behaviour</a> at the University of Exeter.



"Drones can now give us fine details of a landscape - on the scale of individual flowers - and combining this with satellite imagery, we can learn about the food available to pollinators across a large area."



"Along with behavioral studies of insects, this will help us understand the threats they face and how to design conservation programmes.”



Pollinator species, including wild bees, provide key services such as pollinating food crops. Sadly, many pollinator species are in decline.&nbsp;



The research team believes that their work can help protect the great diversity of pollinator species that play vital roles in our ecosystems. This is more urgent now than ever before, as the impacts of climate change on pollinator behavior and habitats are unknown.



"Up to now, most research using satellites has focussed on large-scale agricultural landscapes such as oilseed rape, maize and almond farms," said Gonzales. "We highlight the need to study landscapes with complex communities of plants and pollinators."



"These vary from place to place – and using satellites and drones together is a good way to learn about these local differences.”



The paper is published in the journal <a href="https://www.frontiersin.org/journals/ecology-and-evolution">Frontiers in Ecology and Evolution</a>. The article is part of a special issue called "What sensory ecology might learn from landscape ecology" edited by Brazilian researchers.



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Drones can assist efforts to save bees and other pollinators

A new strategy using technology like satellites and drones can...

Baby sea <a href="https://www.earth.com/news/thousands-of-sea-turtles-still-dying-on-the-east-african-coast/">turtles</a>, including leatherbacks (Dermochelys coriacea), typically hatch at night. The young leatherbacks use the difference of light reflecting off the sea to orient themselves. It’s because of this method of navigation that turtles which hatch near inhabited areas often crawl toward the light from buildings and away from the ocean.&nbsp;



While trying to find the ocean, leatherback babies sometimes crawl in circles. This "circling" behavior depletes energy and leaves the young turtle at greater risk of being picked off by a predator such as a crab or gull.



To understand why circling happens in leatherbacks, researchers at <a href="https://www.fau.edu/">Florida Atlantic University</a> first studied how sensitive the babies are to light. The scientists determined that compared to hard-shelled loggerhead sea turtles, leatherbacks are 10 to 100 times less sensitive to light.



The research, which was published in the journal <a href="https://www.journals.elsevier.com/animal-behaviour">Animal Behaviour</a>, revealed that leatherback circling increased when there was a new moon and the night sky was at its darkest. On the other hand, loggerheads rarely circled, even when they had little light to guide their way. The results are surprising because while leatherbacks feed during both day and night, loggerheads are known to only be active during daylight hours.          



“Leatherback eyes are less sensitive to all wavelengths of light than loggerheads, and during a dark night, they experience difficulty in determining the location of the seaward horizon,” said study first author Samantha Trail.



“Even so, leatherback hatchlings eventually crawl to the sea, even during new moon. It just takes them longer because they stop occasionally to circle, which we think enables them to re-evaluate, and eventually confirm, the correct crawl direction.”



The real question is why leatherback turtles would remain less sensitive to light when it's so important for their survival. From an evolutionary perspective this is a major cost.&nbsp;



The scientists theorize that leatherbacks haven’t evolved more light sensitivity because their difference in vision has other benefits. Perhaps having less light sensitive eyes allows them to better find prey, mates or suitable habitat - which is possible because loggerheads live in different parts of the ocean.&nbsp;&nbsp;



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By <a href="mailto:zachfitzner@yahoo.com">Zach Fitzner</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Baby leatherbacks are blind to the ocean

Baby sea turtles, including leatherbacks (Dermochelys coriacea), typically hatch at...

Humans rely on a variety of cues to identify their friends, including their voices and smiles, or the way they talk. Biologists have long known that dolphins too can form close friendships with their conspecifics, and they can identify their friends by their unique whistles. Now, a research team led by the <a href="https://www.st-andrews.ac.uk/">University of St Andrews</a> in Scotland has found that <a href="https://www.earth.com/earthpedia-articles/are-bottlenose-dolphins-really-that-smart/">bottlenose dolphins</a> also rely on a very surprising cue to recognize their pals: the taste of their urine.



The researchers conducted a series of experiments on captive dolphins at the <a href="https://dolphinquest.com/">Dolphin Quest</a> facilities in Hawaii and Bermuda, where they knew which dolphins were familiar with each other based on who had lived together for at least five years. By pouring both familiar and unfamiliar urine samples into a pool, they discovered that dolphins spent about three times longer investigating the familiar urine than the unfamiliar one.



“We still know very little about how the sense of taste works in dolphins,” said study senior author Vincent Janik, a professor of Biology at the University of St Andrews. “Other studies have shown that they lost a lot of the common tastes that we find in other mammals such as sour, sweet, umami, or bitter. But they have unusual sensory cells on their tongue that are probably involved in this detection of individual tastes of other animals.”&nbsp;&nbsp;



“It is likely that dolphins use a lipid taste receptor to identify urine cues in their fellow dolphins,” added study lead author Jason Bruck, an assistant professor of Physical and Social Ecology at the <a href="https://www.sfasu.edu/">Stephen F. Austin State University</a> in Texas, who conducted this research during a fellowship at the University of St. Andrews.&nbsp;



In order to test whether dolphins had a paired understanding of other dolphins’ cues – if their whistles and urine were connected in their minds – Professor Bruck and his colleagues performed an “expectation violation” experiment, in which they exposed dolphins to incorrect urine-whistle combinations.&nbsp;



While the dolphins did not pay much attention in the case of mismatches, when they encountered a correct urine-whistle pair, they explored the area for an average of 10 seconds longer. These results suggest that dolphins can identify conspecifics by taste alone, but can also integrate information from acoustic and taste inputs.&nbsp;&nbsp;



Future research is needed to clarify the mechanisms through which dolphins use gustatory cues to identify their conspecifics, and to investigate how commercial and industrial chemicals might affect dolphins’ “urine cuing.”&nbsp;



“We may find that oil spills, chemical runoff and other human effects can impede the dolphins’ natural ability to chemically signal to one another. This might prevent males from identifying reproductively capable females or diminish dolphins’ abilities to recognize individuals through honest signals,” Professor Bruck concluded.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.abm7684">Science Advances</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Dolphins recognize their friends by the taste of their urine

Humans rely on a variety of cues to identify their...

Caring for insects as pets may sound strange, but thousands of people all over the world already have praying mantises and other stick <a href="https://www.earth.com/news/scientists-have-found-a-terrifying-decline-in-flying-insects/">insects</a> as pets, according to a new report from <a href="https://pensoft.net/">Pensoft Publishers</a>.



Praying mantises are gaining popularity and fueling a largely unknown market. They are sold at fairs and pet markets, or collected in the wild and then reared by amateurs or professionals.&nbsp;



Some are elegant, with flower-like coloration (the Orchid Mantis, Hymenopus coronatus), and some resemble Pokémons (the Jeweled Flower Mantis, Creobroter wahlbergii). Surprisingly, some of these creatures can even be cuddled (the Giant Shield Mantis Rhombodera basalis).



When selecting an insect as a pet, features such as shape, size, colors, and behaviors are considered. Customers also shop for species that are rare or easy to care for.&nbsp;



It is important to understand how this market, which is largely unregulated, is changing. This could be crucial to conserve rare species and promote awareness of their habitat and place in the ecosystem.



Now, researchers have published a <a href="https://doi.org/10.3897/jor.31.71458">first overview</a> of the praying mantis pet market. The research team includes Roberto Battiston of Museo di Archeologia e Scienze Naturali G. Zannato (Italy), William di Pietro of the World Biodiversity Association (Italy) and entomologist Kris Anderson (USA).&nbsp;



The study authors surveyed 200 hobbyists, professional sellers in the mantis community from 28 different countries. The results showed that the targets of this market are indeed predictable. The typical mantis breeder or enthusiast is 19 to 30 years old, prefers beautiful species over rare ones, and is willing to spend over $30 per insect.&nbsp;



The researchers identified buyers as “mostly curious enthusiasts with poor knowledge of the market dynamics and the laws behind it, even if they seem to generally care about their pet.”



But the data suggests the trade is not always legal. One out of four instances lack permits or transparency from the seller. To ensure these species are conserved in nature, the researchers emphasize that collaboration between scientists and the insect pet community should be considered.&nbsp;



The biology, distribution, and threats to insects are largely unknown. Many species are still waiting to be discovered. This is a big limit to conservation, since you cannot protect what you don’t know.



“Hobbyists and pet insect enthusiasts are producing and sharing a huge quantity of observations on the biology and ecology of hundreds of species, even rare or still undescribed ones, a priceless heritage for the scientific community,” said the researchers.&nbsp;



“Strengthening the dialogue between them, promoting a white market over a black one, may be a crucial help for the conservation of these insects, fundamental parts of the biodiversity of our planet, that are replacing our traditional pets at home.”



The research is published in the <a href="https://jor.pensoft.net/">Journal of Orthoptera Research</a>.



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Praying mantises are becoming more popular as pets

Caring for insects as pets may sound strange, but thousands...

A new study published in the journal <a href="https://zslpublications.onlinelibrary.wiley.com/doi/epdf/10.1111/acv.12788">Animal Conservation</a> has provided the first global evaluation of all terrestrial vertebrate species that have not been declared <a href="https://www.earth.com/news/pink-pigeons-need-a-genetic-rescue-to-survive-extinction/">extinct</a> in order to identify which of these species have not been spotted for at least 50 years, and are thus considered to be “lost,” but perhaps not yet fully extinct. By reviewing information on 32,802 species from the IUCN Red List, the experts have identified 562 such lost species.



The IUCN considers a species as extinct “when there is no reasonable doubt the last individual of a species has died,” and declared a total of 311 terrestrial vertebrate species as extinct since 1500. However, according to the study authors, extinction declarations are rare, partly due to inherent uncertainties in knowing when the last individual of the species has died. 



"This has led to the growth of a group of ‘lost’ species that have not been observed in decades or even centuries, yet are not declared extinct, and as such possess an uncertain conservation status," said the researchers.



From the 562 species that are considered lost, the Red List categorizes 75 as “possibly extinct.” Among this list, <a href="https://www.earth.com/news/one-in-five-reptiles-is-currently-at-risk-of-extinction/">reptiles</a> lead the way with 257 lost species, followed by 137 species of amphibians, 130 of mammals, and 38 of birds. Most of these species were last spotted in megadiverse countries such as Indonesia (69 species), Mexico (33), and Brazil (29).



While not surprising, this distribution of lost species is particularly worrying. “The fact most of these lost species are found in megadiverse tropical countries is worrying, given such countries are expected to experience the highest numbers of extinctions in the coming decades,” explained study lead author Thomas Martin from the <a href="https://www.paigntonzoo.org.uk/">Paignton Zoo</a> in the United Kingdom.



According to study senior author Arne Mooers, a professor of Biodiversity at the<a href="https://www.sfu.ca/"> Simon Fraser University</a>, future survey efforts concentrated on the identified “hotspots” where the existence of many species is uncertain are needed to either rediscover lost species or to remove the reasonable doubt that a particular lost species actually still exists. 



“While theoretical estimates of ongoing ‘extinction rates’ are fine and good, looking hard for actual species seems better,” Professor Mooers concluded.&nbsp;



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

More than 500 animal species are lost, but are they extinct?

A new study published in the journal Animal Conservation has...

Octopoteuthis rugosa

Taxonomic tree: