Battle of the Bites: ‘King of the Dinosaurs’ Bite Was Weaker than Tiny Finch

Tyrannosaurus rex evolved to have a bite that was less powerful in relation to its body size than a tiny Galapagos ground finch, new research has found.

The study, led by scientists at the University of Reading alongside researchers at the University of Lincoln has shown that the T-rex’s evolution was not driven by a need for a powerful bite to kill its prey. The dinosaur’s bite force of 57,000 Newtons was in fact average for its 8 tonne body mass.

In comparison, a Galapagos large ground finch was found to have the most powerful bite in relation to its body size of all of the animals in the study with a bite force of 70 Newtons and an average body mass of just 33 grammes. Pound-for-pound, this makes the bite force of the finch around 320 times more powerful than T-rex.

Scientists used supercomputers to analyse the largest ever collection of bite force data from 434 species both extinct and surviving, including reptiles, birds and mammals. They investigated the theory that animals with more powerful bites were forced to rapidly evolve that way due to changes to their diets.

They instead found that the bite power of most of these animals developed proportionally to evolutionary changes to their body size over time, with only some seeing their bite forces develop at a faster rate than other changes.

Accelerated bursts of bite power evolution were seen in some animals, especially finches – a species famously first noted as an example of natural selection by Charles Darwin. However, expected increases along with body size during the passage of time was seen to be the most common driver of this trait. For example, research showed that the finch’s powerful bite evolved in less than one million years, much faster than that of T-rex which took tens of millions of years.

The team even observed more dramatic reductions in bite forces during evolution than increases. This was true for early humans, whose bite power decreased rapidly despite their body size increasing over time.

The research also suggests human intelligence may have led to us having an extremely weak bite due to the evolution of our larger brains which take up space in our heads where the muscles critical for hard biting would otherwise be.

Marcello Ruta a palaeontologist from the University of Lincoln’s School of Life Sciences and co-author of the study said: “Exactly 180 years ago, Charles Darwin wrote his preliminary notes on the extraordinary variation in bill shape among the Galapagos finches he had discovered a few years earlier. At that time, fossils of the fearsome T. rex had not yet been unearthed. How curious that such humble creatures – the finches – which contributed so much to Darwin’s thinking, would add a new unexpected spin to our understanding of the forces (and bite forces) behind evolution”

Dr Manabu Sakamoto, biological scientist at the University of Reading and lead author of the study, said: “The image of T. rex with its fierce jaws has helped it become the most iconic of dinosaurs, but our research shows its bite was relatively unremarkable. Bite force was not what gave T. rex its evolutionary advantage, as was previously presumed.

“Large predators like T. rex could generate enough bite force to kill its prey and crush bone just by being large, not because they had a disproportionately powerful bite. This counters the idea that an exceptionally strong need for a powerful bite drove these ancient beasts to evolve bone-crushing bite forces.”

Dr Chris Venditti, University of Reading, co-author on the study, said: “Our research provides new insight into the latest theories about the speed and drivers of evolution. It also allows us to create some fascinating hypothetical match-ups.”

The authors argue that the study, published in the Royal Society journal Proceedings B, shows the course of evolutionary history should not be ignored when looking at how animals developed distinctive traits.

Article reblogged from: https://www.lincoln.ac.uk/news/2019/01/1504.asp

Genome sequencing could help conserve declining turtle dove populations

For the first time, scientists have sequenced and assembled the genetic code of the turtle dove in order to help conserve one of the UK’s fastest declining bird species. Working together on this project: Senior Lecturer Dr Jenny Dunn and the Wellcome Sanger Institute, plus collaborators.

You can find out more about this fascinating news online: https://www.sanger.ac.uk/news/view/bird-migration-and-conservation-clues-robin-and-turtle-dove-genomes

 

Student Trip to South Africa Enhances Conservation and Ecology Skills

As part of their studies at the University of Lincoln, students from the School of Life Sciences visited Mankwe wildlife reserve in South Africa in June 2018.

During their stay, the group of staff and students were able to explore the stunning South African landscape whilst carrying out scientific research on the health, behaviour, welfare, conservation and ecology of the wildlife in this biodiversity hotspot.

In the beautiful and fragile ecosystem of Mankwe, students and staff worked alongside a group of  local community-level conservationists. Throughout their trip, students learnt and developed field and identification skills as well as finding out about reserve management and anti-poaching strategies.  In addition, they were able to apply skills and knowledge gained during their degree programme to develop a self-driven research project on an aspect of animal health, behaviour and/or ecology.

Mankwe is a 4750 hectare reserve in the North West Province of South Africa, approximately 5km east of Pilanesberg National Park. The accommodation is a selection of safari tents, wooden cabins and a clinker brick chalet at the Waterbuck camp, where students have the opportunity to experience a true bush adventure. There are no fences so students live among the wildlife.

To find out more information about the School of Life Sciences Overseas Field Trips, click here.

Garden Seed Influences Young Turtle Doves’ Survival Chances

Young turtle doves raised on a diet of seeds from non-cultivated arable plants are more likely to survive after fledging than those relying on food provided in people’s gardens, new research into Britain’s fastest declining bird species has shown.

Ecologists at the University of Lincoln, UK, investigated the dietary habits of adult and nestling European turtle doves – an IUCN Red List Threatened Species – breeding in the UK, using DNA analysis of faecal samples. They found significant associations between the body condition and the diet of the bird.

Nestling turtle doves still being fed by their parents were found to thrive on seeds foraged from non-cultivated arable plants such as scarlet pimpernel and chickweed, but the birds were in poorer condition when their diet was high in seeds provided by humans in back gardens or public spaces. In contrast, adult body condition was better when more cultivated seeds such as wheat, oil seed rape and barley were present in the diet.

Data collected for the study, which was carried out in collaboration with the Royal Society for the Protection of Birds (RSPB), the University of Sheffield and Cardiff University, was compared with the results of previous studies carried out in the 1960s and 1990s. It revealed a fundamental shift in the diet of turtle doves, showing that the birds are now relying more heavily on food found in gardens, such as sunflower and niger seeds, than they did 50 years ago.

As the UK’s fastest declining bird species, the results of the study have important implications for conservation strategies to save the turtle dove. Previous research has shown that nestling birds with better body condition are more likely to survive after fledging and strategies should be developed to provide the correct diet for the bird at each stage of its life.

Dr Jenny Dunn, Lecturer in Animal Health and Disease in the University of Lincoln’s School of Life Sciences, led the research while based at the RSPB. She said: “Turtle doves are the UK’s fastest declining bird, with a loss of 98% of breeding birds since 1970. Researchers are trying to tackle the problem by identifying ways to provide food resources for the species while they are breeding in the UK, but for this to be effective we need to understand the birds’ food sources and the impact they have on both adults and their young.

“The results of this study suggest that conservation strategies should include provision of anthropogenic seeds for adults early in the breeding season, coupled with habitat rich in accessible seeds from arable plants once chicks have hatched.”

To understand the diet of the birds, researchers caught turtle doves on breeding grounds at 11 sites across East Anglia, and extracted DNA from the faecal samples which enabled them to identify the diet of each bird. Their body condition was also examined, and nest sites monitored.

Further research is now needed to link the findings of the study to the use of habitats provided for turtle doves through agri-environment schemes.

The study was part-funded by the RSPB, Natural England and the NERC Biomolecular Analysis Facility at the University of Sheffield.

The full paper, ‘The decline of the turtle dove: dietary associations with body condition with other columbids analysed using high throughput sequencing’ has been published in the journal Molecular Ecology and can be viewed online at: https://onlinelibrary.wiley.com/doi/abs/10.1111/mec.14766

Dr Soulsbury’s research featured at NHM symposium

On the 11th and 12th of November 2017 London’s Natural History Museum hosted HumaNature, a co-sponsored conference between World Extreme Medicine (WEM), the Society for Experimental Biology, brought together experts in the fields of medicine and animal physiology. Our School’s Senior Lecturer, Dr Carl Soulsbury, delivered a talk about his extensive research. 

The symposium was established by WEM’s founder Mark Hannaford and Prof. Craig Franklin- Deputy Head of the School of Biological Sciences / Executive Director of Research Ethics, University of Queensland. The 2 day event provided an opportunity for attendees to share research, best practice and techniques between the worlds of human and animal medicine.

A summary of Dr Soulsbury’s talk can be found below.

Exercising to the limit (and more) in birds

Many organisms carry out exercise as part of their daily lives, be it through behaviours such as finding food, reproducing or avoiding predators. In birds, many species carry out impressive physical feats such as long distance migration, flying at high altitudes, through to intense, energetically expensive mating displays. Exercise can be viewed both in terms of its intensity and its duration. It is the combination of these that determines how physiologically stressful exercise is. In this talk, I compare the relative contribution of duration and intensity of exercise as determinants of exercise’s costs, and how this in turn impacts individual ageing. Using systems where the amount of intensive exercise pushes individuals to their physiological limits, I demonstrate its negative effect on individual physiology and survival. By using comparisons found in nature, it can provide critical insights into the effects of intense and extreme exercise on the human body.

A podcast featuring a selection of the speakers, including Dr Soulsbury, can be found online (credit to Ben Cattaneo of ‘Allthingsrisk’).