Problems with assumptions in macroecology

Thanks to some very kind and smart colleagues, we have an editorial published in Ecology and Evolution!

https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.5721

Here is the citation:

Justin G. Boyles, Danielle L. Levesque, Julia Nowack, Michał S. Wojciechowski, Clare Stawski, Andrea Fuller, Ben Smit, and Glenn J. Tattersall 2019. An oversimplification of physiological principles leads to flawed macroecological analyses. https://doi.org/10.1002/ece3.5721

Take home message? Few endotherms are homeothermic, so they do not conform to assumptions of the Scholander-Irving model. Taking predictions from the SI model based on a broad range of lab studies can lead to huge errors in predictions. A re-assessment of macroecological predictions using this approach is warranted.

Demonstration of the inherent limitations of using body temperature (Tb) and the lower critical temperature (Tlc) of the thermal neutral zone to calculate thermal conductance (C) when Tb and Tlc are poorly defined.

Congratulations Anne Yagi!

Congratulations to Anne Yagi for her Blue Racer Award from the Canadian Herpetological Society. The Blue Racer award is presented to an individual in recognition of cumulative contributions to the conservation of amphibians and reptiles in Canada. 

For full details on the announcement:

https://8trees.ca/news/f/canadian-herpetological-society-honors-8trees-inc-president?fbclid=IwAR3FdYgO-FzXHJvmlnMafhH6Scb6qJiqKCz35iCbLoYZDJhw77bhTyWZiUA

Bridgeman now the Master

When he left the lab to write up his thesis, he was but the learner…now, HE is the Master.

Congratulations, Justin Bridgeman for a successful defence! Justin’s thesis earlier today was on “Behavioural thermoregulation and escape behaviour in the round goby”.

Thanks to the selfless efforts of the committee members (Dr. Gaynor Spencer, Dr. Liette Vasseur, and Dr. Patricia Wright), external examiner (Dr. Dennis Higgs, U Windsor), and committee chair (Dr. Cheryl McCormick).

Thank to all the lab mates for supporting Justin and welcoming him back for his brief visit.

All the best in the future Justin! We look forward to the manuscripts…and for a place to crash when we visit you in Halifax! 😉

Toucans of the atlantic

Earlier this summer, I was lucky enough to visit the Isle of May, Scotland to fulfill a long-time ambition to collect thermal image data on puffins in the wild. Ever since we published our work on the toucan in 2009, I have wanted to study the puffins, examining evidence for elevated capacity to control or distribute body heat through their uniquely colourful bill. Living in a cool climate with a large radiator like their bill presents a unique opportunity to test our hypotheses. In spring of 2018 I managed to visit the Elliston, Newfoundland puffin colony to start this project, but the distance to view a little too far to obtain high quality results.

Well, the short story is that they do show an extraordinary capacity to do so! Here is just a sample image (from the 200 Gb of videos):

Active and basking Atlantic puffins show capacity for intense heat transfer to the bill. The one above has recently landed back at the colony, presumably foraging although in this case, there is no evidence of food. Other images show cool bills, as we have seen in many other bird species, demonstrating the vasomotor control over blood flow to the bill is a fairly generalised phenomenon.
Infrared thermal video of an Atlantic puffin in May 2018 – early arrival at nest and investigating burrows.
Atlantic puffin in the rain.

If I only had the time to conduct the data analysis, I could put some numbers on these values. I certainly have my work cut out for me, examining those returning from the water with food vs. those basking and resting. I have a few other thoughts about these data that I hope to extract.

Many thanks must go to the town of Elliston, Newfoundland and the Atlantic puffin colony there, the Centre for Ecology and Hydrology (UK), the Isle of May (Scotland) Scientists, and especially Mark Newell for hosting me at the Isle of May, and Mike Harris for introducing us. Sorry it took so long to post this.

Further Reading

Tattersall, GJ, Arnaout, B, and Symonds, MRE.  2017.  The evolution of the avian bill as a thermoregulatory organ. Biological Reviews 92: 1630-1656. doi:10.1111/brv.12299

Greenberg, R, Cadena, V, Danner, RM, and Tattersall GJ. 2012. Heat loss may explain bill size differences between birds occupying different habitats. PLoS One, 7: e40933. 

Symonds, MRE and Tattersall, GJ. 2010. Geographical variation in bill size across bird species provides evidence for Allen’s rule.American Naturalist. 176: 188-197.

Tattersall, GJ, Andrade, DV, and Abe, AS. 2009. Heat exchange from the toucan bill reveals a controllable vascular thermal radiator.Science, 325: 468-470.

Delayed homeothermy in high-atltitude deer mice

Congratulations to Cayleih Robertson for her paper that just came out today in the Proceedings of the Royal Society B, entitled:

Development of homeothermic endothermy is delayed in high-altitude native deer mice (Peromyscus maniculatus)

This project is the result of Cayleih’s PhD research in Dr. Grant McClelland’s lab. I was lucky enough to be involved with these talented scientists, although all the credit goes to Cayleih for her hard work. What a tour de force of physiology, biochemistry and imaging.

Sample video of the experimental paradigm examining cooling in neonatal mice using infrared thermal imaging. For more details, see the link to the paper above.

Backyard Biology

Earlier this year, I put a raspberry pi on a robin nest in my backyard. Used it as an opportunity to test out tweet streaming from my twitter account, so am posting the link here to the lab blog. Sorry it took so long, I was away from stable internet access for the past month.

Insect thermogenesis

A luna moth was on our window outside the department yesterday.

So, we brought it inside for a lab show and tell. Shivering up a storm….

Thorax temperature up to 32C, while the abdomen temperature was still below 20C (the lab was ~21C, and the moth had been briefly placed in a cold fridge).

CSZ 2019

Another year passes and another good Canadian Society of Zoologists meeting.

Here is Nick Sakich presenting his first scientific poster. Well done Nick! Nick had a lot of attention at his poster. Maybe we can get Nick to come to CSZ next year!

And here is a rogue’s gallery of happy scientists congratulating Cayleih Robertson (second from right) for winning the Hoar Award for the best student presentation at the CSZ! Cayleih is studying her PhD in Dr. Grant McClelland’s (left) lab, conducted her MSc with Dr. Patricia Wright (second from left), and her undergraduate thesis with Dr. Suzie Currie (middle). I (far right) have the distinct privilege of being on the receiving end of Cayleih’s collaborative nature, in that she has involved my lab with a portion of her PhD (thus, why I’m in the picture!). Full credit has to go to Cayleih for her spirit of inclusivity, scientific curiosity, and intelligence. And of course, she gave a great talk! Congratulations, Cayleih!

Student-driven research

A few months ago, my MSc student, Nick Sakich, received notice that he was successful in receiving a Company of Biologists Travelling Fellowship to continue his collaborative work he began while a student at the University of Guelph.

Congratulations, Nick!

He will be visiting Aruba in June to finish up his research. Although envious of journey, we all know he has a lot in store for him in planning for the trip and wish him all the success.

Shape Shifting Birds – PhD Opportunity

Please consider applying for this PhD Opportunity in Australia to work with my colleague, Dr Matthew Symonds on Shape-Shifting Birds.

This research forms part of an ARC Discovery Project (PI: Symonds; CI: Klassen & Tattersall) whose goal is to determine whether changes in body shape are an evolutionary response to climate change. Endothermic animals (such as birds) have a range of adaptations for dealing with the temperatures they experience. One such adaptation is body shape: birds in warmer climates tend to have large extremities (bills and legs), increasing their surface area and enabling loss of excess heat. Adaptations to climate (and hence climate change) can occur quickly, and there is evidence of significant increases in bird extremities in recent years – a novel potential consequence of climate change. Whether this represents an evolutionary response to climate change is unknown, nor do we know what characteristics make specific bird species liable to respond to climate change in this way, or what the likely consequences of such responses are.

The student will undertake an extensive comparative analysis of Australian birds, designed to identify a) which bird species are showing changes in body shape (bill and leg morphology); b) what ecological (life- history, behaviour, habitat) factors determine such responses; c) whether these changes relate to fitness/survival and d) whether such changes are linked to long-term populations trends in Australian birds.

The project will involve extensive work in Australian museum collections, measuring bird morphology using traditional and modern (3D-scanning) techniques. There is also a strong analytical component, involving use of long-term field data on Australian bird species as well as phylogenetic comparative analysis of large-scale ecological data sets for Australian birds.

Please send an application letter, together with your CV, to Dr Matthew Symonds (matthew.symonds@deakin.edu.au).

Further information can be found in our review papers:

Symonds, MRE and Tattersall, GJ. 2010. Geographical variation in bill size across bird species provides evidence for Allen’s rule.American Naturalist. 176: 188-197.

Tattersall, GJ, Arnaout, B, and Symonds, MRE.  2017.  The evolution of the avian bill as a thermoregulatory organ. Biological Reviews 92: 1630-1656. doi:10.1111/brv.12299