On Thursday we saw the arrival of a couple of lab visitors from Italy. Stefano Marras (left) is a longtime friend and collaborator while Luca Pettinau is a Master's student who will be visiting our lab for three months. While here they'll be working on a project looking at how trait variation within fish schools influences shoal cohesion.
Introducing the newest iteration of our miniature trawl simulator - MiniTrawl 3.0. Kudos to Davide Thambithurai, Jack Hollins, and Travis van Leuween for tweaking the design up until this point. This version includes a special rear compartment to shield captured fish from the oncoming flow, plus lower and upper escape areas in the trawl mouth. This photo shows a school of zebrafish swimming ahead of the trawl net. As they tire or turn they are captured in the net unless they are able to find an escape route. This setup is being used in our laboratory simulations of trawling to determine why some fish are more vulnerable to capture than others.
This week Shaun visited Toulouse to give a seminar at the CNRS Laboratoire Evolution & Diversité Biologique. While there Shaun was hosted by Libor Zvorka, Julien Cucherousset (@JCucheFish), and new Killen lab post-doc Barbara Koeck. Thanks to all for a fantastic visit with lots of stimulating conversation, cool research ideas, and of course lots of beer!
This week Shaun visited friends and colleagues Katja Enberg and Christian Jörgensen in Bergen, Norway. While there he gave at talk at the Institute of Marine Research and drank far too much whiskey. Thank you Katja and Christian for being such amazing hosts!
Yesterday Shaun Killen made the not-so-long trek to Edinburgh to participate in a double-bill seminar set focusing on nature-inspired engineering. The event was organised by Ignazio Viola (School of Engineering, University of Edinburgh) and Shaun spoke alongside Kiran Ramesh (School of Engineering, University of Glasgow). Kiran, Ignazio, and Shaun have recently received funding from a Carnegie Collaborative Grant to examine how fish swimming biomechanics may help inform the design and arrangement of wave power turbines.
The seminar event was a lot of fun with some great discussion with people in attendance from both engineering and biological sciences. Unfortunately for Shaun, however, he was dismayed when Kiran informed him that large dragons could never fly with flapping wings because the the power of the leading edge vortices required to provide the lift would need to be so powerful that they would basically tear the wings from the body. Dreams shattered.
This week Shaun Killen spent a few days at University College Cork, Ireland, where he was visiting the lab of Thomas Reed. It was a fantastic few days with lots of great conversations (and a few pints) with the students and staff of the School of Biological, Earth and Environmental Sciences. While there Shaun gave a talk on our recent work looking at links between sociability and metabolic traits in fish.
Jan, Shaun, and Julie before a bit of mid-day bubbly.
Massive congratulations to newly minted PhD Julie Nati on surviving her viva yesterday! Julie is from Luxembourg and joined our lab 4 years ago. She was co-supervised by Jan Lindström and her thesis was on the role of physiology in invasiveness in fish species. Not only did she complete an excellent thesis (one paper from the thesis published so far, here, and several others on the way) but she somehow survived being Shaun's first ever PhD student. Congrats Julie!
A fondant bullhead in a respirometer, to carry on our long-held institute tradition of study-species inspired viva cakes!
We have a post-doc vacancy to focus on questions related to evolutionary developmental biology and genomics including the genetic and epigenetic basis of phenotypic change. The project takes place within our highly interdisciplinary group and has generous support from a recently awarded NERC Highlight topics grant to Dr Kevin J. Parsons (PI), Prof Neil B. Metcalfe, Dr Shaun S. Killen and Dr Jan Lindström.
The project provides an opportunity to take evo-devo and genomics in a new direction by investigating the impact that long-term exposures to varying thermal regimes can have on evolution. The postdoc will be in charge of leading and applying large-scale population genomic and QTL mapping approaches to sticklebacks that have evolved within geothermally-heated and ambient temperature locations in Iceland. A substantial portion of this research will also involve the use of genomics to understand patterns of methylation in response to temperature in both wild and lab-reared populations. While these genomic approaches will be used, the lab is phenotype-first orientated and works at the intersections of ecology, evolution, physiology, and development.
See also the lab website of Kevin Parsons to get a broader feel for the ideas of techniques that will be involved in this research.
Deadline is January 8, 2017! To apply click here and search for reference 015558.
Davide Thambithurai recently returned from a trip to Trondheim, Norway, where he visited the lab of Fredrik Jutfelt at the Norwegian University of Science and Technology. While there he gave a talk about his recent experiments on the vulnerability of individual fish to passive fishing methods.
Shaun Killen recently returned from a two-week stint working with colleagues Suzie Mills and Ricardo Beldade at CRIOBE (shown above), on the beautiful Tahitian island of Moorea in French Polynesia. Accompanying Shaun was IBAHCM Research Fellow Tommy Norin, who will remain in Moorea until mid-December (poor guy).
Tommy, Shaun, and Ricardo doing plankton tows to feed the young clownfish (photo Tommy Norin).
The main focus of the collaboration is to study the factors that influence the dispersal of clownfish larvae after they hatch and leave their nest. In particular, the aim was to see how the metabolism and swimming ability of the larvae changes throughout their early development, to understand whether the little guys are able to control their own destiny by swimming faster than the prevailing currents.
A 15-day old clownfish larvae in a teeny tiny respirometer.
Getting ready to collect some clownfish eggs to take back to the lab for hatching and larval rearing.
Adult clownfish. (Photo Tommy Norin)
Clownfish eggs. The bright orange colour indicates they were likely laid within the last day or two. (Photo Tommy Norin)
These eggs are much older and likely close to hatching. You can even see the eyeballs of the embryos inside. (Photo Tommy Norin)
Tommy and Shaun checking out some clownfish nests. (Photos Suzie Mills)
Harvested eggs back in the lab, being aerated until they hatch.
Other projects underway with the team include understanding how anenomes affect routine oxygen uptake in their resident clownfish, and studies to examine how various environmental stressors affect metabolic rate in sea hares.
A juvenile clownfish being measured for oxygen uptake with the respirometry chamber being placed within an anenome. (Photo Tommy Norin)
Seahare oxygen uptake being measured in respirometry chambers. (Photo Tommy Norin)
Atmospheric carbon dioxide (CO2) is expected to more than double by the end of the century. The resulting changes in ocean chemistry (ocean acidification) will affect the behaviour, sensory systems and physiology of a range of fish species. Although a number of past studies have examined effects of CO2 in social fish species, most have assessed individuals in social isolation, which can alter individual behaviour and metabolism in social species. Within social groups, a learned familiarity can develop following a prolonged period of interaction between individuals, with fishes preferentially associating with familiar conspecifics because of benefits such as improved social learning and greater foraging opportunities. In a new study, Lauren Nadler, Shaun Killen, and colleagues at the Lizard Island Research Station and James Cook University find that exposure to increased dissolved CO2 causes a reduction in the tendency of green chromis damselfish to prefer to shoal with familiar fish. Even under elevated CO2, however, the presence of shoal-mates causes an apparent “calming effect” for individual fish, detectable via a reduction in metabolic rate. These results provide insight into some of the effects of rising CO2 levels and ocean acidification on shoaling behaviours in fish which are crucial for their ability to find food and avoid predators. Read more in the OPEN ACCESS paper here:
http://conphys.oxfordjournals.org/…/4/1/cow052.full.pdf+html
Nadler LE, Killen SS, McCormick MI, Watson S-A, Munday PL (2016) Effect of elevated carbon dioxide on shoal familiarity and metabolism in a coral reef fish. Conserv Physiol 4(1): cow052; doi:10.1093/conphys/cow052
The maximum aerobic metabolic rate (MMR) of fish sets an upper limit on their ability to perform physiological functions associated with physical activity, growth, and reproduction. While there is increasing interest in the significance of MMR for the ecology of fish, and particularly their ability to cope with climate change, there are currently two main methods used to estimate MMR (namely, measuring oxygen uptake either DURING and AFTER inense exercise) with a limited understanding of whether these methods give differing results. In a new meta-analysis of literature data for 121 fish species, Shaun Killen, Tommy Norin and Lewis Halsey find that these methods tend to give similar estimates for MMR within and among species. Read more in the open access article here:
http://onlinelibrary.wiley.com/doi/10.1111/jfb.13195/epdf
Killen S.S., Norin, T., Halsey, L.G. 2016. Do method and species lifestyle affect measures of maximum metabolic rate in fish? Journal of Fish Biology. DOI: 10.1111/jfb.1319
Recently we welcomed Mar Pineda to our lab group. Mar is a placement student from the University of Manchester and will be with us for the net 9 months. During this time she will be studying how temperature affects the spatial positioning of individual fish within swimming schools. Welcome Mar!
I'm pleased to announce a new post-doc opening with some engineering colleagues (Dr Kiran Ramesh, University of Glasgow and Dr Ignazio Viola, University of Edinburhg) for a project that will examine how the movements of swimming fish may be used to inspire mechanisms of electric power generation from moving water. The job will require knowledge in computational and experimental fluid dynamics. Familiarity with biomechanics will be a bonus. More information is available from the University of Glasgow e-Recuitment page, job reference 014847.
Ectothermic animals are strongly influenced by temperature. It is speculated that species face a trade-off between increased performance at a specific temperature versus being able to function over a broader range of temperatures but at a lower peak level. The balance of this trade-off – if it exists – may influence the environments that fish and other ectotherms inhabit and how they respond to climate change. A new paper by Julie Nati, Jan Lindstrom, Lewis Halsey and Shaun Killen shows that, across fish species, peak performance for aerobic scope is not linked to performance across a range of temperatures, suggesting that links between peak and thermal breadth for the capacity for aerobic metabolism may not affect responses to climate warming. Read more in on access paper here!:
http://rsbl.royalsocietypublishing.org/content/12/9/20160191
Nati, JH, Lindstrom, J, Halsey, LG, & Killen, SS. 2016. Is there a trade-off between peak performance and performance breadth across temperatures for aerobic scope in teleost fishes? Biology Letters. DOI: 10.1098/rsbl.2016.0191
Many animal species live in groups to derive benefits for foraging and predator avoidance. Another potential benefit is a reduction in routine energy expenditure for each individual within the group as they share duties for anti-predator vigilance. There may also be a ‘calming effect’, whereby individuals in group experience decreased stress and energy expenditure compared to isolated individuals. In a new study on the cover of this month’s Journal of Experimental Biology, Shaun Killen, Lauren Nadler, and colleagues at James Cooke University in Australia examined these issues by measuring metabolic and growth rates in individual damselfish (Chromis viridis) with and without visual and olfactory cues from groups of other fish of the same species. They found that individuals in shoals reduced their metabolic rate by 26% from their metabolic rate when alone. As increased extreme weather events may lead to forced social isolation in gregarious fishes, this could have repercussions for individual energy budgets. Photo credit: Eva McClure. Read more in the open access article here!:
http://jeb.biologists.org/content/219/18/2802
Nadler, L.E., Killen, S.S., McClure, E.C., Munday, P.L., McCormick, M.I. 2016. Shoaling reduces metabolic rate in a gregarious coral reef fish species. Journal of Experimental Biology. 219: 2802-2805. doi: 10.1242/jeb.139493
I am currently searching to fill a 3 year postdoc position in my lab for an ongoing ERC funded project looking at the role of physiological traits in fisheries-induced evolution (deadline October 16, 2016). The project involves a mix of lab and field work, measurements of physiological traits (e.g. metabolic rates, swimming performance), and the use of acoustic telemetry to track fish movements and responses to deployed gears in the wild. The postdoc will work alongside a team of other postdocs, PhD students, technicians, and research staff at the Institute of Biodiveristy, Animal Health, and Comparative Medicine at the University of Glasgow. Find out more info here!
Individuals within animal species often show wide variation in behavioural traits, such as willingness to explore novel habitats or take risks around predators. This behavioural variation is often correlated with other traits including body size or metabolic rate. In a new study by Shaun Killen and colleagues in Germany, it was observed that for juvenile zebrafish, the tendency of individuals to take risks was explained by variation in body length but not necessarily body mass or baseline metabolic demand.
Read more in the open access article in the Journal of Fish Biology, here!:
http://onlinelibrary.wiley.com/doi/10.1111/jfb.13100/full
Polverino, G., Bierbach, D., Killen, S.S., Uusi-Heikkilä, S., Arlinghaus, R. 2016. Body length rather than routine metabolic rate and body condition correlates with risk-taking behaviour in juvenile zebrafish (Danio rerio). Journal of Fish Biology. doi:10.1111/jfb.13100
Recent evidence suggests that the Greenland shark may be the longest lived of all vertebrates, living for hundreds of years and not even reaching sexual maturity until they are at least 130 years old. How are they able to live this long? A new study by David Costantini, Shona Smith, Shaun Killen, and colleagues in Denmark examined this issue by measuring the oxidative status of Greenland shark tissues to see if minimising oxidative damage might be a mechanism by which they are able to extend their life. Although indices of protein damage in Greenland sharks are very low compared to most other animal species, it appears that this may be associated with other aspects of the ecology of Greenland sharks (e.g. adaptation to life in cold water and repeated deep dives) and not related for their long lifespan. Read more here!:
http://www.sciencedirect.com/science/article/pii/S1095643316302276
Costantini, D., Smith, S., Killen, S. S., Nielsen, J., & Steffensen, J. F. (2016). The Greenland shark: A new challenge for the oxidative stress theory of ageing?. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology.
Congratulations to PhD student Davide Thambithurai on receiving a small research grant from the Fisheries Society of the British Isles! Davide will be using the grant to study the heart rates of embryonic and larval fish.