Biology

A “bizarre” armoured dinosaur, Spicomellus afer, with 1 metre spikes sticking out from its neck

By ScientifiCult 27 August 2025

New fossils show how “bizarre” armoured dinosaur, Spicomellus afer, had 1 metre spikes sticking out from its neck

Research fossils show that the famous tail weapons of ankylosaurs evolved much earlier than previously thought

The world’s most unusual dinosaur is even stranger than first realised…

Today, research published in Nature reports that Spicomellus afer had a tail weapon more than 30 million years before any other ankylosaur, as well as a unique bony collar ringed with metre-long spikes sticking out from either side of its neck.

Spicomellus is the world’s oldest ankylosaur, having lived more than 165 million years ago in the Middle Jurassic near what is now the Moroccan town of Boulemane. It was the first ankylosaur to be found on the African continent.

The province Fes Meknes, within which the Boulemane Province has been located since 2015. Picture by Rherrad, CC BY-SA 4.0

New remains of Spicomellus found by a team of palaeontologists have helped to build upon the original description of the unusual animal. The initial description of the species was published in 2021 and was based on one rib bone. The team now know that the animal had bony spikes fused onto and projecting from all of its ribs, a feature not seen in any other vertebrate species living or extinct. It had long spikes, measuring 87 centimetres, which authors believe would have been even longer during the animal’s life, that emerged from a bony collar that sat around its neck.

Prof Susannah Maidment of Natural History Museum, London, and the University of Birmingham, who co-led the team of researchers said, “To find such elaborate armour in an early ankylosaur changes our understanding of how these dinosaurs evolved. It shows just how significant Africa’s dinosaurs are, and how important it is to improve our understanding of them.”

“Spicomellus had a diversity of plates and spikes extending from all over its body, including metre-long neck spikes, huge upwards-projecting spikes over the hips, and a whole range of long, blade-like spikes, pieces of armour made up of two long spikes, and plates down the shoulder. We’ve never seen anything like this in any animal before”

“It’s particularly strange as this is the oldest known ankylosaur, so we might expect that a later species might have inherited similar features, but they haven’t.”

Project co-lead, Professor Richard Butler of the University of Birmingham, said, “Seeing and studying the Spicomellus fossils for the first time was spine-tingling. We just couldn’t believe how weird it was and how unlike any other dinosaur, or indeed any other animal we know of alive or extinct. It turns much of what we thought we knew about ankylosaurs and their evolution on its head and demonstrates just how much there still is to learn about dinosaurs”.

Authors postulate that this array of spikes would have been used for attracting mates and showing off to rivals. Interestingly, similar display armour has not yet been found in any other ankylosaur, with later species possessing armour that probably functioned more for defence.

One explanation for this is that as larger predatory dinosaurs evolved in the Cretaceous, as well as bigger carnivorous mammals, crocodiles and snakes, the rising risk of predation could have driven ankylosaur armour to become simpler and more defensive.

One feature of early ankylosaurs that may have survived, however, is their tail weaponry. While the end of Spicomellus’ tail hasn’t been found, the bones that do survive suggest that it had a club or a similar tail weapon.

Some of the tail vertebrae are fused together to form a structure known as a handle, which has only been found in ankylosaurs with a tail club. However, all these animals lived millions of years later in the Cretaceous.

Authors of the study believe that the combination of a tail weapon and an armoured shield that protected the hips suggest that many of the ankylosaurs’ key adaptations already existed by the time of Spicomellus.

The discovery reinforces the importance of the fossil record in solving evolutionary puzzles and deepening our understanding of the geographic distribution of dinosaurs. It also helps to spark public imagination in dinosaurs as we learn more about the baffling characteristics of species like Spicomellus.

Professor Driss Ouarhache, lead of the Moroccan team from the Université Sidi Mohamed Ben Abdellah who co-developed the research, says, “This study is helping to drive forward Moroccan science. We’ve never seen dinosaurs like this before, and there’s still a lot more this region has to offer.”

The Spicomellus afer remains that form the basis of this study were cleaned and prepared at the Department of Geology of the Dhar El Mahraz Faculty of Sciences in Fez, Morocco, using scientific equipment provided by the University of Birmingham’s Research England International Strategy and Partnership Fund. The fossils are now catalogued and stored on this site.

The paper ‘Extreme armour in the world’s oldest ankylosaur’ is available now in Nature.

This research is part of the Natural History Museum’s Evolution of Life Research Theme that seeks to reveal the causes and consequences of evolutionary and environmental change, which is central to understanding life on Earth. It is also a contribution from the Earth Heritage Network at the University of Birmingham, which seeks to develop new ways to use palaeontological resources for the benefit of society.

Bibliographic information:

Maidment, S.C.R., Ouarhache, D., Ech-charay, K. et al. Extreme armour in the world’s oldest ankylosaur, Nature (2025), DOI: https://doi.org/10.1038/s41586-025-09453-6

Press release from the University of Birmingham.

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First transfer of behavior between species through single gene manipulation

By ScientifiCult 14 August 2025

First transfer of behavior between species through single gene manipulation

Scientists strengthen brain cell connections to enable gift-giving courtship behavior in fruit flies.

Researchers in Japan have genetically transferred a unique courtship behavior from one fruit fly species to another. By turning on a single gene in insulin-producing neurons, the team successfully made a species of fruit fly (Drosophila melanogaster) perform a gift-giving ritual it had never done before. The study, published in the journal Science, represents the first example of manipulating a single gene to create new neural connections and transfer behavior between species.

Scientists have successfully transferred gift-giving courtship behavior from Drosophila subobscura to D. melanogaster males. They genetically engineered insulin-producing neurons in D. melanogaster to produce FruM proteins, causing these cells to grow long neural projections and connect to the courtship center in the brain. Picture Credits: Tanaka et al., 2025, CC BY First transfer of courtship behavior between species of fruit flies, through single gene manipulation; the study is published in the journal Science — Scientists have successfully transferred gift-giving courtship behavior from Drosophila subobscura to D. melanogaster males. They genetically engineered insulin-producing neurons in D. melanogaster to produce FruM proteins, causing these cells to grow long neural projections and connect to the courtship center in the brain. Picture Credits: Tanaka et al., 2025, CC BY

In nature, most male fruit flies court mates by rapidly vibrating their wings to create sound patterns or “courtship songs.” However, Drosophila subobscura has evolved a very different strategy: males regurgitate food and offer it as a gift to females during courtship. This behavior does not exist in closely related species such as D. melanogaster.

Drosophila subobscura males regurgitate food and offer it as a gift to females during courtship. Picture Credits: Tanaka et al., 2025, CC BY

These two fruit fly species diverged about 30-35 million years ago. Both have a gene called “fruitless” or “fru” that controls courtship behavior in males, but they use different strategies—one species sings and the other gives gifts. The researchers found the reason for this difference: in gift-giving flies (D. subobscura) insulin-producing neurons are connected to the courtship control center in the brain, while in singing flies (D. melanogaster) these cells remain disconnected.

“When we activated the fru gene in insulin-producing neurons of singing flies to produce FruM proteins, the cells grew long neural projections and connected to the courtship center in the brain, creating new brain circuits that produce gift-giving behavior in D. melanogaster for the first time,” Dr. Ryoya Tanaka, co-lead author and lecturer at Nagoya University’s Graduate School of Science, explained.

First transfer of courtship behavior between species of fruit flies, through single gene manipulation; the study is published in the journal Science. The researchers identified 16-18 insulin-producing neurons in Drosophila subobscura that express the male-specific protein FruM. When they activated FruM expression in insulin-producing neurons in D. melanogaster, these cells grew new neural connections and successfully transferred gift-giving courtship behavior to this species for the first time. Picture Credits: Tanaka et al., 2025, CC BY

The researchers inserted DNA into D. subobscura embryos to create flies with heat-activated proteins in specific brain cells. They used heat to activate groups of these cells and compared the brains of flies that did and did not regurgitate food. They identified 16-18 insulin-producing neurons that make the male-specific protein FruM, clustered in a part of the brain called the pars intercerebralis.

“Our findings indicate that the evolution of novel behaviors does not necessarily require the emergence of new neurons; instead, small-scale genetic rewiring in a few preexisting neurons can lead to behavioral diversification and, ultimately, contribute to species differentiation,” Dr. Yusuke Hara, co-lead author from the National Institute of Information and Communications Technology (NICT), noted.

“We’ve shown how we can trace complex behaviors like nuptial gift-giving back to their genetic roots to understand how evolution creates entirely new strategies that help species survive and reproduce,” senior author Dr. Daisuke Yamamoto from NICT said.

The study, “Cross-species implementation of an innate courtship behavior by manipulation of the sex-determinant gene” was published in the journal Science, on August 14, 2025, at DOI: 10.1126/science.adp5831. It represents the result of collaborative efforts led by Drs. Yusuke Hara and Daisuke Yamamoto at the National Institute of Information and Communications Technology (NICT), in partnership with researchers at Nagoya University.

Funding:

This research was conducted with support from KAKENHI Grant-in-Aid for Scientific Research: “Early-Career Scientists (Project Numbers: 19K16186, 21K15137),” “Scientific Research A (Project Number: 21H04790),” “Transformative Research Areas (A): Hierarchical Bio-Navigation Science (Project Numbers: 22H05650, 24H01433),” and “Scientific Research C (Project Number: 23K05846).”

Press release from Nagoya University

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Small shelly fauna biodiversity: fossils from archaeocyathid reef systems, such as the lower Cambrian Harkless Formation

By ScientifiCult 12 June 2025

Small shelly fauna biodiversity: fossils from archaeocyathid reef systems – University of Missouri study challenges assumptions about biodiversity near Earth’s first reef systems, such as the lower Cambrian Harkless Formation, found in Nevada.

Rocky outcrops that contain the ancient reefs. Photo courtesy Sarah Jacquet

More than 514 million years ago, long before dinosaurs roamed the Earth, sponge-like creatures called archaeocyathids were already busy building some of the planet’s earliest reefs — just north of Death Valley in present-day Nevada.

Emily Edwards collects rock samples from the ancient reefs. Photo courtesy Sarah Jacquet

In a recent study, University of Missouri researchers looked at how these ancient reef-building organisms shaped their environment. They also studied tiny, fossilized sea creatures called “small shelly fauna” — some of the earliest animals with hard shells ever found on Earth.

Various small shelly fossils recovered from the beds surrounding the Cambrian reefs. Scale bar is 1 mm. Photo courtesy Sarah Jacquet Small shelly fauna biodiversity: fossils from archaeocyathid reef systems, such as the lower Cambrian Harkless Formation — Small shelly fauna biodiversity: fossils from archaeocyathid reef systems, such as the lower Cambrian Harkless Formation. In the picture, various small shelly fossils recovered from the beds surrounding the Cambrian reefs. Scale bar is 1 mm. Photo courtesy Sarah Jacquet

Modern coral reefs are known as biodiversity hotspots, teeming with marine life and supporting entire ecosystems. But this study found that early reefs did not appear to boost biodiversity in the same way, Casey Bennett, a graduate student in the Department of Geological Sciences and lead author on the study, said.

“With modern reefs, biodiversity is expected to decrease as you move away from the reef structure due to reduced shelter and food access,” she said. “However, we didn’t find a consistent pattern with these ancient reefs — instead, it was pretty inconsistent and was largely dependent on localized conditions.”

This discovery offers a glimpse into how life evolved in early oceans and challenges assumptions about how ecosystems develop around reef structures. It’s a reminder that not all reefs are created equal, and understanding their ancient forms could offer insight into how modern marine systems might change.

Ancient ocean currents — and rocks

To conduct the study, the team analyzed fossil assemblages across multiple rock sections. Their results show a relatively low-diversity but high-abundance community, with some organisms dominating certain layers —possibly shaped by ancient ocean currents.

Sarah Jacquet, an assistant professor of paleontology in Mizzou’s College of Arts and Science and co-author on the study, believes hydrodynamics, or how water moved around the reef, played a significant role.

“Potentially, this happened by preferentially removing or keeping certain faunas, rather than the reef serving as a major food source for surrounding organisms,” she said.

Additionally, sediment conditions, including the type of rock, impacted the quality of fossil preservation.

“Different rock types around the reef appeared to represent different ‘sub environments’ that tended to preserve certain organisms better than others, leading to localized patches of specific fossil groups,” Bennett said.

The team emphasizes the need for continued fieldwork and fossil analysis to piece together how early reef habitats influenced the spread and organization of life in Earth’s oceans.

“Just because we know how the world works today doesn’t mean it worked the same way back then,” Jacquet said. “This research helps us step back and appreciate how life evolved under very different conditions.”

Casey Bennett and Emily Edwards sit below the ancient reefs with bags of rock samples collected from their field work. Photo courtesy Sarah Jacquet

Bibliographic information:

Casey C. Bennett, Clare Mate, Sarah M. Jacquet, Small shelly fauna biodiversity from reef-adjacent facies of the lower Cambrian Harkless Formation, Nevada, Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 669 2025, 112922, ISSN 0031-0182, DOI: https://doi.org/10.1016/j.palaeo.2025.112922

Press release from University of Missouri, by Eric Stann

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Chimpanzee groups drum with distinct rhythms

By ScientifiCult 9 May 2025

Chimpanzee groups drum with distinct rhythmsNew research from a team of cognitive scientists and evolutionary biologists finds that chimpanzees drum rhythmically, using regular spacing between drum hits. Their results, publishing in the Cell Press journal Current Biology on May 9, show that eastern and western chimpanzees—two distinct subspecies—drum with distinguishable rhythms. The researchers say these findings suggest that the building blocks of human musicality arose in a common ancestor of chimpanzees and humans.

“Based on our previous work, we expected that western chimpanzees would use more hits and drum more quickly than eastern chimpanzees,” says lead author Vesta Eleuteri (@EleuteriVesta) of the University of Vienna, Austria. “But we didn’t expect to see such clear differences in rhythm or to find that their drumming rhythms shared such clear similarities with human music.”

Earlier studies showed that chimpanzees produce low-frequency sounds by drumming on buttress roots—large, wide roots that grow above the soil. The researchers suggest that the chimps use these percussive patterns to send information over both long and short distances.

“Our previous study showed that each chimpanzee has their own unique drumming style and that drumming helps to keep others in their group updated about where they are and what they’re doing—a sort of way to check in across the rainforest,” Eleuteri says. “What we didn’t know was whether chimpanzees living in different groups have different drumming styles and whether their drumming is rhythmic, like in human music.”

To find out, Eleuteri and her team, including senior authors Catherine Hobaiter of the University of St. Andrews in the UK and Andrea Ravignani of Sapienza University in Rome, teamed up with other chimpanzee researchers to study 371 drumming bouts in 11 chimpanzee communities, including six populations and two subspecies.

Chimpanzee drumming. Photo Credits: Current Biology, Eleuteri et al. — Chimpanzee groups drum with distinct rhythms, according to a new study published in the journal Current Biology. In the picture, a chimpanzee drumming. Photo Credits: Current Biology, Eleuteri et al.

After analyzing the drum patterns, they found that chimpanzees drum with rhythm and that the timing of their hits is non-random and often evenly spaced. Eastern and western subspecies also exhibited different drumming patterns; western chimpanzees used evenly spaced hits while eastern chimpanzees more often alternated between hits at shorter and longer time intervals. They also found that western chimpanzees hit their “drums” more, using a faster tempo, and integrated their drumming earlier in their pant-hoot vocalizations.

“Making music is a fundamental part of what it means to be human—but we don’t know for how long we have been making music,” says Hobaiter. “Showing that chimpanzees share some of the fundamental properties of human musical rhythm in their drumming is a really exciting step in understanding when and how we evolved this skill. Our findings suggest that our ability to drum rhythmically may have existed long before we were human.”

###

This research was supported by funding from the European Union’s 8th Framework Programme, Horizon 2020, the Austrian Science Fund, the Swiss National Science Foundation, SNSF Eccellenza Professorial Fellowship, Homerton College, Newnham College, the A.H. Schultz Foundation, the Jane Goodall Institute Schweiz, MEXT, the Max Plank Society, the European Union ERC, TOHR, the Center for Music in the Brain, and the Danish National Research Foundation.

Bibliographic information:

Vesta Eleuteri, Jelle van der Werff, Wytse Wilhelm, Adrian Soldati, Catherine Crockford, Nisarg Desai, Pawel Fedurek, Maegan Fitzgerald, Kirsty E. Graham, Kathelijne Koops, Jill Pruetz, Liran Samuni, Katie Slocombe, Angela Stoeger, Michael L. Wilson, Roman M. Wittig, Klaus Zuberbühler, Henry D. Camara, Gnan Mamy, Andrea Ravignani, Catherine Hobaiter, “Chimpanzees drum rhythmically and with subspecies variation”, “Current Biology” (2025) DOI: https://doi.org/10.1016/j.cub.2025.04.019

Press release from Cell Press.

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Evolution and paleoecology of mosasaurs (Sarabosaurus dahli)

By ScientifiCult 12 December 2024

New insights into the evolution and paleoecology of mosasaurs (Sarabosaurus dahli): most comprehensive study to date

Iconic extinct marine lizards continue to surprise us

Mosasaurs are extinct marine lizards, spectacular examples of which were first discovered in 1766 near Maastricht in the Netherlands, fueling the rise of the field of vertebrate palaeontology (the study of fossil remains of animals with backbones). Palaeontologist Michael Polcyn presented the most comprehensive study to date on the early evolution and ecology of these extinct marine reptiles. On 16 December 2024, Polcyn will receive his PhD from Utrecht University for his research into the evolution of the mosasaurs.

“Mosasaurs are a textbook example of macroevolution, the emergence of new and distinct groups of animals, above the level of species. Although they have been studied for centuries, new discoveries, novel research approaches, and the application of technology, are still teaching us about their relationships and behaviors, some of which continues to surprise us. For example, through the use of detailed comparative anatomy aided by micro-CT scanning technology, we have gained a much better understanding of what group of lizards mosasaurs likely evolved from.”

Additionally, use of these advanced imaging technologies has allowed him to study the internal structures of the braincases of mosasaurs, and sort out the early evolutionary relationships of some previously problematic fossil taxa.

“This study not only addressed the early evolution of the group, but also explored small- and large-scale aspects of their feeding biology,” Polcyn continued. “One spectacular example was a specimen I discovered in Angola, that had the remains of three other mosasaurs in its stomach, one of which was the same taxon as the predator, and documented the first occurrence of cannibalism in mosasaurs.”

To the sea

Mosasaurs belong to a group of lizards that took to the sea about 100 million years ago (just like the ancestors of the whales later did). Throughout their 34-million-year history, they evolved into well-adapted marine animals that occupied a wide variety of niches and habitats. Together with a large number of other species, they became extinct 66 million years ago, in the aftermath of the meteorite impact that also wiped out the dinosaurs.

“A relatively large number of fossils are known from the second half of the evolutionary history of mosasaurs, allowing a good understanding of the relationships among those species, which have been classified into four major groups,” says Polcyn. “Much less is known about their early evolutionary history, and how those major groups are related to one another, their origins, and the origin of mosasaurs as a whole.”

To address these gaps, Polcyn has focused on bringing new discoveries to light and restudying historical specimens with advanced imaging technologies, providing significant new anatomical information that is used to infer phylogenetic relationships. Polcyn’s work helps resolve a long-running scientific debate, concluding mosasaurs are not very closely related to snakes, but supporting the idea that their closest relatives are near the monitor lizards.

You are what you eat

Not much was previously known about the feeding habits of mosasaurs either, but a small, yet no less remarkable gap in that knowledge was filled with the discovery, by Polcyn in Angola, of a fossilized mosasaur with three other mosasaurs in its stomach, one being the same species as the predator.

“Whether that mosasaur was a scavenger or actively hunted its prey cannot be said with certainty; however, we do have the first documented example of cannibalism in mosasaurs. Additionally, we gained insights into how mosasaurs processed their prey, and relative body size of prey and predator.”

Also included in his dissertation is a large-scale study of the feeding behaviour of mosasaurs, looking at how mosasaurs divided their foraging areas through the evolutionary history of the group. Polcyn integrated previously published data, along with a new, very large sample that covered a period from 92 to 66 million years ago and included finds from all over the world. The result of that study illuminate patterns of foraging area segregation, and feeding diversity in mosasaurs.

About

Polcyn’s entry into palaeontology followed a non-traditional academic path. After serving in the U.S. submarine service and a career in technology and engineering, he devoted himself to research on extinct vertebrates, with a focus on marine reptiles. He is currently a Senior Research Fellow at ISEM at Southern Methodist University in Dallas, Texas.

mosasaurs Sarabosaurus dahli life reconstruction. Credits: Andrey Atuchin — New insights into the evolution and paleoecology of mosasaurs (Sarabosaurus dahli): the most comprehensive study to date. Sarabosaurus dahli life reconstruction. Credits: Andrey Atuchin

Press release from Utrecht University

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Bottlenose dolphins “smile” at each other while playing

By ScientifiCult 2 October 2024

Bottlenose dolphins “smile” at each other while playing

bottlenose dolphins smile when playing I delfini si "sorridono" a vicenda durante il gioco — Bottlenose dolphins (Tursiops truncates) use the “open mouth” facial expression—analogous to a smile—to communicate when playing. Photo Credits: © ZooMarine, Roma

Dolphins are extremely playful, but little is known about how they—and other marine mammals—communicate during playtime. New research publishing October 2 in the Cell Press journal iScience shows that bottlenose dolphins (Tursiops truncates) use the “open mouth” facial expression—analogous to a smile—to communicate during social play. The dolphins almost always use the facial expression when they are in their playmate’s field of view, and when playmates perceived a “smile,” they responded in kind 33% of the time.

“We’ve uncovered the presence of a distinct facial display, the open mouth, in bottlenose dolphins, and we showed that dolphins are also able to mirror others’ facial expression,” says senior author and evolutionary biologist Elisabetta Palagi (@bettapalagi) of the University of Pisa. “Open-mouth signals and rapid mimicry appear repeatedly across the mammal family tree, which suggests that visual communication has played a crucial role in shaping complex social interactions, not only in dolphins but in many species over time.”

Dolphin play can include acrobatics, surfing, playing with objects, chasing, and playfighting, and it’s important that these activities aren’t misinterpreted as aggression. Other mammals use facial expressions to communicate playfulness, but whether marine mammals also use facial expressions to signal playtime hasn’t been previously explored.

“The open mouth gesture likely evolved from the biting action, breaking down the biting sequence to leave only the ‘intention to bite’ without contact,” says Palagi. “The relaxed open mouth, seen in social carnivores, monkeys’ play faces, and even human laughter, is a universal sign of playfulness, helping animals—and us—signal fun and avoid conflict.”

To investigate whether dolphins visually communicate playfulness, the researchers recorded captive bottlenose dolphins while they were playing in pairs and while they were playing freely with their human trainers.

They showed that dolphins frequently use the open mouth expression when playing with other dolphins, but they don’t seem to use it when playing with humans or when they’re playing by themselves. While only one open mouth event was recorded during solitary play, the researchers recorded a total of 1,288 open mouth events during social play sessions, and 92% of these events occurred during dolphin–dolphin play sessions. Dolphins were also more likely to assume the open mouth expression when their faces were in the field of view of their playmate—89% of recorded open mouth expressions were emitted in this context—and when this “smile” was perceived, the playmate smiled back 33% of the time.

“Some may argue that dolphins are merely mimicking each other’s open mouth expressions by chance, given they’re often involved in the same activity or context, but this doesn’t explain why the probability of mimicking another dolphin’s open mouth within 1 second is 13 times higher when the receiver actually sees the original expression,” says Palagi. “This rate of mimicry in dolphins is consistent with what’s been observed in certain carnivores, such as meerkats and sun bears.”

The researchers didn’t record the dolphins’ acoustic signals during playtime, and they say that future studies should investigate the possible role of vocalizations and tactile signals during playful interactions.

“Future research should dive into eye-tracking to explore how dolphins see their world and utilize acoustic signals in their multimodal communication during play,” says corresponding author and zoologist Livio Favaro (@LivioF_80). “Dolphins have developed one of the most intricate vocal systems in the animal world, but sound can also expose them to predators or eavesdroppers. When dolphins play together, a mix of whistling and visual cues helps them cooperate and achieve goals, a strategy particularly useful during social play when they’re less on guard for predators.”

Bibliographic information:

Maglieri et al., “Smiling underwater: exploring playful signals and rapid mimicry in bottlenose dolphins”, iScience, DOI: http://dx.doi.org/10.1016/j.isci.2024.110966

Press release from Cell Press.

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Dwarf lemurs are coming out of winter’s slumber; here’s why scientists are excited

By ScientifiCult 16 March 2021

An unusual creature is coming out of winter’s slumber; here’s why scientists are excited

Duke Lemur Center recreates the seasonal swings of native habitat, helping to unlock the secrets of hibernation

The fat-tailed dwarf lemurs are our closest hibernating relative. Researchers at the Duke Lemur Center have been changing up their care to more closely match the seasonal fluctuations they experience in the wild. Researchers at the Duke Lemur Center have been changing up their care to more closely match the seasonal fluctuations they experience in the wild. Photo by David Haring, Duke Lemur Center

DURHAM, N.C. — If you binged on high-calorie snacks and then spent the winter crashed on the couch in a months-long food coma, you’d likely wake up worse for wear. Unless you happen to be a fat-tailed dwarf lemur.

This squirrel-sized primate lives in the forests of Madagascar, where it spends up to seven months each year mostly motionless and chilling, using the minimum energy necessary to withstand the winter. While zonked, it lives off of fat stored in its tail.

Animals that hibernate in the wild rarely do so in zoos and sanctuaries, with their climate controls and year-round access to food. But now our closest hibernating relative has gone into true, deep hibernation in captivity for the first time at the Duke Lemur Center.

“They did not disappoint,” said research scientist Marina Blanco, who led the project. “Indeed, our dwarf lemurs hibernated just like their wild kin do in western Madagascar.”

The researchers say recreating some of the seasonal fluctuations of the lemurs’ native habitat might be good for the well-being of a species hardwired for hibernation, and also may yield insights into metabolic disorders in humans.

“Hibernation is literally in their DNA,” Blanco said.

Blanco has studied dwarf lemurs for 15 years in Madagascar, fitting them with tracking collars to locate them when they are hibernating in their tree holes or underground burrows. But what she and others observed in the wild didn’t square with how the animals behaved when cared for in captivity.

Captive dwarf lemurs are fed extra during the summer so they can bulk up like they do in the wild, and then they’ll hunker down and let their heart rate and temperature drop for short bouts — a physiological condition known as torpor. But they rarely stay in this suspended state for longer than 24 hours. Which got Blanco to wondering: After years in captivity, do dwarf lemurs still have what it takes to survive seasonal swings like their wild counterparts do? And what can these animals teach us about how to safely put the human body on pause too, slowing the body’s processes long enough for, say, life-saving surgery or even space travel?

To find out, Duke Lemur Center staff teamed up to build fake tree hollows out of wooden boxes and placed them in the dwarf lemurs’ indoor enclosures, as a haven for them to wait out the winter. To mimic the seasonal changes the lemurs experience over the course of the year in Madagascar, the team also gradually adjusted the lights from 12 hours a day to a more “winter-like” 9.5 hours, and lowered the thermostat from 77 degrees Fahrenheit to the low 50s.

The animals were offered food if they were awake and active, and weighed every two weeks, but otherwise they were left to lie.

It worked. In the March 11 issue of the journal Scientific Reports, the researchers show for the first time that fat-tailed dwarf lemurs can hibernate quite well in captivity.

For four months, the eight lemurs in the study spent some 70% of their time in metabolic slow-motion: curled up, cool to the touch, barely moving or breathing for up to 11 days at a stretch, showing little interest in food — akin to their wild counterparts.

Now that spring is afoot in North Carolina and the temperatures are warming, the lemurs are waking up. Their first physical exams after they emerged showed them to be 22% to 35% lighter than they were at the start but otherwise healthy. Their heart rates are back up from just eight beats per minute to about 200, and their appetites have returned.

“We’ve been able to replicate their wild conditions well enough to get them to replicate their natural patterns,” said Erin Ehmke, who directs research at the center.

Females were the hibernation champs, out-stuporing the males and maintaining more of their winter weight. They need what’s left of their fat stores for the months of pregnancy and lactation that typically follow after they wake up, Blanco said.

Study co-author Lydia Greene says the next step is to use non-invasive research techniques such as metabolite analysis and sensors in their enclosures to better understand what dwarf lemurs do to prepare their bodies and eventually bounce back from months of standby mode — work that could lead to new treatments for heart attacks, strokes, and other life-threatening conditions in humans.

Blanco suspects the impressive energy-saving capabilities of these lemurs may also relate to another trait they possess: longevity. The oldest dwarf lemur on record, Jonas, died at the Duke Lemur Center at the age of 29. The fact that dwarf lemurs live longer than non-hibernating species their size suggests that something intrinsic to their biological machinery may protect against aging.

“But until now, if you wanted to study hibernation in these primates, you needed to go to Madagascar to find them in the act,” Blanco said. “Now we can study hibernation here and do more close monitoring.”

This research was supported by the Duke Lemur Center.

CITATION: “On the Modulation and Maintenance of Hibernation in Captive Dwarf Lemurs,” Marina B. Blanco, Lydia K. Greene, Robert Schopler, Cathy V. Williams, Danielle Lynch, Jenna Browning, Kay Welser, Melanie Simmons, Peter H. Klopfer, Erin E. Ehmke. Scientific Reports, March 11, 2021. DOI: 10.1038/s41598-021-84727-3.

Press release from Duke University, by Robin A. Smith.

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Alien frog invasion wreaks havoc on natural habitat

By ScientifiCult 5 June 2020

Alien frog invasion wreaks havoc on natural habitat

A warning on World Environment Day

The spotted-thighed frog is easily identified by the distinct spots on its thighs. Credits: UniSA/Christine Taylor

Indiscriminate feeding by an alien population of the carnivorous spotted-thighed frog – could severely affect the native biodiversity of southern Australia according to a new study by the University of South Australia.

The invasive amphibian – Litoria cyclorhyncha – which has hitchhiked across the Nullarbor from Western Australia – has now established a community of 1000-plus in Streaky Bay, South Australia, with sightings also confirmed on the Eyre Peninsula and at the Adelaide airport.

This is the first study of the spotted-thighed frog’s diet in its invaded range with the findings providing important biological information about the impact of the alien species on natural ecosystems.

Ecology experts, UniSA’s Associate Professor Gunnar Keppel and Christine Taylor, say the potential of the spotted-thighed frog spreading to other parts of Australia is very concerning given its destructive eating patterns.

“This frog is an indiscriminate eating machine that will devour just about anything it can fit into its mouth,” Taylor says.

“We’re talking about a relatively large, predatory tree frog that, as a species is alien to South Australia, and it could have devastating impact on invaded habitats.

“As it eats away at local species, it’s impacting the natural ecosystem, which can displace or destroy local food webs, outcompete native birds, reptiles and mammals for resources, and potentially change natural biodiversity.”

Biodiversity is the theme of this year’s United Nations World Environment Day.

Published in the Australian Journal of Zoology, the study examined the stomach contents of 76 spotted-thighed frogs across three habitats – an artificial wetland, seminatural bushland and an urban setting.

The carnivorous spotted-thighed frog will indiscriminately devour just about anything it can fit into its mouth. Credits: UniSA/Christine Taylor

On average, each frog had at least six prey items in its stomach, with prey estimated to include 200 different species, 60 per cent of which were beetles, spiders and insects. Native geckos, young frogs and mice were also identified as prey.

Introduced species can have terrible outcomes for Australia, if not understood well. The infamous introduction of the cane toad in the 1930s as a mechanism to control sugar cane beetles, is just one example. The failure of that initiative continues to ravage Australia’s ecology, with the cane toad now listed as a threatening pest under the Environment Protection and Biodiversity Conservation Act.

Assoc Prof Keppel says it is important that people understand how detrimental introduced species can be for whole environments. He warns that if the spread of the spotted-thighed frog is not kept under control they could dominate many ecosystems in south-east Australia, at the expense of the local flora and fauna.

“The spotted-thighed frog is obviously very mobile. Already it’s managed to travel more than 2000 kilometres and set up a colony in Streaky Bay. But its considerable tolerance of salinity and potential ability to withstand high temperatures could lead to further geographic spread, and if not controlled, it could extend further eastward into the Murray-Darling Basin,” Assoc Prof Keppel says.

“It’s vital that we continue to protect Australia’s biodiversity. Preventing further dispersal of the spotted-thighed frog is a high conservation priority.

“The state government should consider managing the invasive population of spotted-thighed frogs at Streaky Bay. This should include education programs to inform people about what to do if they find a frog, as well as the feasibility of exterminating the population in South Australia.

“Importantly, if you do see one of these critters in your travels – leave it be. We don’t want it hitchhiking any further.”

Press release from the University of South Australia

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