New research explores the effect of winter dormancy on cold-blooded cognition

New research explores the effect of winter dormancy in cold-blooded cognition

Unlike mammals, amphibians who rest up during the winter do not forget the memories they made beforehand – this is the surprising discovery of new scientific research.

New research explores the effect of winter dormancy in cold-blooded cognition
New research explores the effect of winter dormancy in cold-blooded cognition
Photo: Johannes Hloch

The new study, published in the journal Scientific Reports, reveals that the processes involved in winter dormancy may have a fundamentally different impact on memory in amphibians and mammals.

Researchers from the University of Lincoln, UK, and two universities in Vienna, Austria, discovered that brumation – the period of winter dormancy that is observed in cold-blooded animals, similar to the process of hibernation in mammals – does not seem to adversely affect the memory of salamanders.

This key finding differs dramatically from previous studies of mammals, which show that hibernation often causes animals to forget some of the memories they formed prior to their period of inactivity.

Dr Anna Wilkinson, from the School of Life Sciences at the University of Lincoln, led the study in collaboration with colleagues from the University of Vienna and the University of Veterinary Medicine Vienna.

Dr Wilkinson said: “Long-term torpor is an adaptive strategy that allows animals to survive harsh winter conditions. However, the impact that this has on cognitive function is poorly understood. We know that in mammals, hibernation causes reduced synaptic activity and can cause them to lose some of the memories they formed prior to hibernation, but the effect of brumation on memory has been unexplored, until now.”

The researchers trained twelve salamanders to navigate a maze and remember the path they needed to take to reach a reward. Half of the animals were then placed into brumation for 100 days, while the other half remained under normal keeping conditions.

A post-brumation memory retention test revealed that animals from both conditions recalled how to navigate the maze.

“We demonstrated that each of the animals solved the task using memory, rather than sensory cues such as smell of the reward, and we’re therefore confident that the period of brumation did not impact on their ability to remember,” Anne Hloch, another author on the paper explained. “For these animals, memory retention is essential for survival as it allows them to recall important information about the environment, such as the location of food and the presence of predators.”

The researchers suggest that the differences in retention observed between mammals and amphibians could be caused by their different learning and memory processes, or the nature of their torpor. Mammals regularly rouse from their hibernation and enter intervals of sleep, whereas cold-blooded animals are dependent on the temperature of their surroundings during brumation and are therefore forced to stay torpid until temperatures rise.

The paper is available to read online.

New research sheds light on why plants change sex

Plants with a particular breeding system change their sex depending on how much light they receive, new scientific research has revealed.

Cranesbill (Pixabay image)

The ability of plants to flower one year as male and the next as female, or vice versa, is well documented in ‘dioecious’ plants, however the causes of this ability to change gender have been largely unexplored in ‘gynodioecious’ plants until now.

Gynodioecy is a breeding system that is found in certain flowering plant species in which female and hermaphroditic plants coexist within a population. Gynodioecy is the evolutionary intermediate stage between hermaphrodite plants (each flower has both male and female parts) and dioecious populations (each plant having either only male or female flowers).

The ability to change sex in response to the environment has been studied extensively in dioecious plants but this new research has revealed that gynodioecious plants also change sex depending on their environment.

The results of a four-year study by researchers at the University of Lincoln, UK, show that the level of light received by the plant has a significant effect on sexual expression and reproductive output. The study found that in habitats with high levels of light, plants were more likely to change their sexual expression, and the researchers believe this is because sex lability (readiness to change) is costly and related to the availability of resources.

Dr Sandra Varga, Marie Curie Research Fellow at the University of Lincoln’s School of Life Sciences, led the research. She explained: “The evolution and maintenance of such sexual polymorphism has been investigated by evolutionary biologists for decades. It is one of the most important developments in the evolution of plant breeding systems. However, understanding the causes and consequences is challenging because so many different factors might be involved in the process of changing from one sex to another.

“Our research clearly showed that sex expression was changeable over the course of the study, and was directly related to light availability.”

Throughout the study, the researchers observed the behaviour of 326 different plants for four years and transplanted them between locations with both high and low light levels to replicate the different environments they may encounter. For example, the wood cranesbill plants used in the study can often be found under dense forest canopies and in meadows and road verges.

The researchers monitored how the sex and reproductive outputs of the plants differed depending on their location, to garner a deeper understanding of how their behaviour is altered by their environment.

The paper is published in the American Journal of Botany and is available to read online.

Reshaping our ideas of bacterial evolution

The shape of bacteria does not influence how well they can move – this is the surprising finding of new research which could have major implications for the future of the scientific and medical industries.

Bacteria

Published in Nature’s new Ecology & Evolution journal, the results refute long-held theories that there should be a strong link between the evolution of shape in bacteria and their ability to move.

Setting them apart from larger living organisms such as fish, seals and whales – for which shape is very important to their ability to swim efficiently – this new discovery highlights the unusual nature of the environment in which bacteria live.

The extensive study was conducted by Dr Fouad El Baidouri and Professor Stuart Humphries from the School of Life Sciences at the University of Lincoln, UK, together with Dr Chris Venditti from the University of Reading and was funded by a Leverhulme Trust Research Leadership Award. The team drew together information on 325 different species of Firmicutes bacteria to help address a gap in global scientific knowledge about how the shape of single-cell organisms like bacteria affects their mobility, lifestyle and pathogenicity (ability to cause disease).

Professor Humphries explained: “Many evolutionary biologists have asked why animals are shaped the way they are, but until now the scientific community has relied on mathematical models to predict the relationship between shape and movement in bacteria. We expected swimming bacteria to be rod-shaped in order to reduce their energy costs, but experimental tests are rare and, surprisingly, analyses of this relationship in an evolutionary context are lacking entirely.

“Our research has produced evidence that these theoretical predictions don’t match reality, at least in this group of bacteria, and it therefore makes a major contribution to our understanding of the evolution of bacteria.”

The researchers employed new ways of exploring the evolution of bacteria to more accurately assess the form and function of the cells.

Dr El Baidouri said: “The main focus of our research is to understand why bacteria come in so many different forms, but in order to understand this we needed to find out which bacteria have which shape. With no datasets available, we saw a clear need to collect morphological and ecological data on bacteria – a task which took several months, and is still ongoing.

“We fully expected to confirm a widely-held belief, backed by strong theoretical predictions, that rod-shaped cells would move more effectively than coccoid (spherical) cells, and that shape and motility had co-evolved. We used a number of approaches to confirm our findings, and to our great surprise we didn’t find any association between the two traits.”

Contrary to recent evidence, the study also found that neither the ability to cause disease nor the lifestyle of these bacteria (whether it is free-living or host-associated) are affected by shape. These results suggest that, for this group of bacteria at least, they have an even greater evolutionary flexibility than previously thought.

Students visit Animal Inside Out exhibition in Newcastle

University of Lincoln Life Sciences students see the world’s most amazing creatures like they’d never seen them before.

The Animal Inside Out: A Body Worlds Production is an unforgettable exhibit featuring real-life animals from gorillas to giraffes, elephants to dogs, all preserved through plastination. This is a process used in anatomy to preserve bodies or body parts, first developed by Gunther von Hagens in 1977.

Our Bioveterinary students were given first priority to sign up for the trip due to the knowledge and information learned in the classroom being mirrored in the anatomical tour.

Over 60 students took a coach up to Newcastle as part of Activities Week, which the School of Life Sciences puts on every year, to see the real-life application of their classroom-learned skills and knowledge.

With over 100 real animal specimens, students got the opportunity to see the nervous, muscular, circulatory, respiratory, digestive and reproductive system structure within the animals, showcasing what really lies beneath nature’s skin.

The exhibit that runs till January 3rd, 2017 aims to show the complexity of animal physiology, looking at the inner workings of the animal systems that enable them to live, thrive and survive.

No animals were hurt or killed for this exhibit.

Dr Colin Butter took some amazing photos of the exhibit which he has shared below

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To find out more about the exhibit visit: http://www.life.org.uk/whats-on/animal-inside-out

All About Bats and Owls: Chris Packham to host FREE Halloween wildlife talk

All About Bats and Owls: Chris Packham leads free Halloween wildlife talkNaturalist and TV presenter Chris Packham will explore the wild side of Halloween with a free-to-attend public lecture and live animal demonstration.On Monday 31st October 2016, Chris – who is a Visiting Professor in the University of Lincoln’s School of Life Sciences – will offer audiences a fascinating insight into the mysterious creatures and animals we traditionally associate with the spooky seasonal celebration.

His talk and demonstration, titled All About Bats and Owls, is free to attend and is open to people of all ages. Places are limited so bookings should be made in advance.

Visitors will learn all about the flying creatures from Chris, who co-hosts the new series of Autumn watch beginning on BBC Two today (Monday 24th October).

He will teach his audience how bats live and help them understand the vital ecological role they play. With support from the Bat Conservation Trust, of which Chris is President, the talk will give audiences the chance to observe a live demonstration of pipistrelle bats.

Chris said: “Bats have so many attributes which tickle the naturalist’s fancy. Many of them look quirky so we are fascinated by their bizarre physiology and, relative to so many other animals, they are inaccessible and this tantalises us as we struggle to know them better.”

Chris will also be joined on stage by Derek Tindall Birds of Prey, who will show a fascinating ensemble of birds including a barn owl, great grey owl, Eurasian eagle owl and African spotted eagle.

The free public event follows the recent ‘BioBlitz’ survey of on-campus flora and fauna, which Chris led as part of his role as Visiting Professor at the University of Lincoln. Chris and students carried out pond dipping, mud and water sampling, bird calling and spotting, and insect and moth trapping to uncover what creatures live in the natural habitats around campus.

All About Bats and Owls is part of the University of Lincoln’s flagship Great Minds free public guest lecture series, which aims to provide inspirational insights into different aspects of society – from the entertainment world to elite sport. Admission is free but prior booking is essential. This season’s Great Minds series has so far included talks from Lord Victor Adebowale CBE, Chancellor of the University of Lincoln and a cross bench member of the House of Lords, and Rory Underwood MBE, one of England’s most successful international rugby players.

For more information about All About Bats and Owls and to book your place, visit the website, email events@lincoln.ac.uk or phone 01522 837100.