A new pied babbler paper has come out from Martha Nelson-Flower. Martha looked at how long subordinates stayed in their groups and how likely they were to gain a dominant breeding position. In babblers there appears to be a sex difference: males have a longer subordinate tenure when they are related to the dominant male, but there is no impact of relatedness for females (either relatedness to the dominant female or male). But why is this important? Well, it turns out that the longer you are a subordinate for then the more likely you are to attain dominance.

Why would this be the case? Well it may be that dominant males are less tolerant of unrelated males, as they are more likely to compete with them for reproductive opportunities. Related males in pied babbler groups tend to be father and son (with dad being dominant), although it can be the case that one brothers holds the dominant position while the other is subordinate. But why would sticking around as a subordinate be better? Surely it pays to leave quickly and get a dominant position elsewhere, so you yourself can breed. However, gaining dominance is not that easy, vacancies are not that easy to come by and you have to be a pretty big and sexy male to just go and kick another male out of his group. Perhaps it is best just to stay in a group, build up your condition and wait for an opportunity, as going it alone is a very risky business for a babbler!

Nepotism and subordinate tenure in a cooperative breeder. Biology Letters
In many cooperatively breeding societies, subordinate individuals delay dispersal and independent breeding. The length of time that subordinates delay dispersal (subordinate tenure) is likely to have important implications for both subordinate and dominant fitness. However, quantitative comparisons of the subordinate tenure of males and females are rare, especially with respect to the presence of same- versus opposite-sex close kin. Here, we investigate subordinate tenure and how it is affected by the genetic relationship between subordinates and dominants in the cooperatively breeding southern pied babbler (Turdoides bicolor). We find that for males, longer subordinate tenures result in increased likelihood of attaining dominance. In the presence of an unrelated dominant male, tenure of subordinate males is significantly shorter, indicating nepotism among males. Female tenures are unaffected by the genetic relationship to either the dominant male or female. These results are some of the first to demonstrate that the sex of both the dominants and subordinates, and the genetic relationship between them, can have significant impacts on subordinate tenure and dispersal delays. Nepotism has likely played a vital role in the evolution of cooperative breeding in this species.

​In a recent blog post I mentioned the research of the Hot Birds Project and the new research into how pied babblers respond to high temperatures that is going on. Amazingly, a new paper which is really relevant to that sort of work has just come out in Science. This research, by Mariette and Buchanan looks at acoustic communication between parents and their offspring in birds. This isn’t the normal adult bird chirping to a chick but communicating to their unhatched offspring. Zebra finches acoustically signal high ambient temperatures (>26°C) to their unhatched embryos, resulting in developmental changes to the offspring. This is brought about solely by using acoustic cues. This type of work is especially exciting because it shows potential coping mechanisms that animals may have for changing climates, it is also an exciting meeting point of parental effects, phenotypic plasticity and climate science. I’ve put the abstract and link to the article at the end of the post.

Link to video to help explain the 'talking to their eggs when hot' paper: http://www.sciencemag.org/news/2016/08/video-zebra-finch-call-prepares-their-eggs-climate-change?utm_source=newsfromscience&utm_medium=facebook-text&utm_campaign=zebrafinch-6739

The other cool paper that has come out recently is work looking at Atlantic canaries and inbreeding. Males who were inbred were worse at singing and females mated less often with inbred males, producing fewer eggs. So for canaries it seems that singing is a honest signal of male genetic quality, adding credence to the ‘good genes’ hypothesis – the idea that male signals are a true representation of their genetic quality and females choose mates for this reason. Work on lizards, mice and lemurs have shown that olfactory cues are linked to genes related to immunity. I love this kind of science, I find it so fascinating. It also has impacts for helping to understand conservation issues with species range and population sizes and how to ensure viable populations. Again, the abstract and link are below.

Mariette & Buchanan (2016) Prenatal acoustic communication programs offspring for high posthatching temperatures in a songbird. Science, 353:812-814
In many species, embryos can perceive and learn external sounds. Yet, the possibility that parents may use these embryonic capacities to alter their offspring’s developmental trajectories has not been considered. Here, we demonstrate that zebra finch parents acoustically signal high ambient temperatures (above 26°C) to their embryos. We show that exposure of embryos to these acoustic cues alone adaptively alters subsequent nestling begging and growth in response to nest temperature and influences individuals’ reproductive success and thermal preferences as adults. These findings have implications for our understanding of maternal effects, phenotypic plasticity, developmental programming, and the adaptation of endothermic species to a warming world.

De Boer et al. (2016) ‘Out of tune’: consequences of inbreeding on bird song. Proc Roy Soc B
The expression of bird song is expected to signal male quality to females. ‘Quality’ is determined by genetic and environmental factors, but, surprisingly, there is very limited evidence if and how genetic aspects of male quality are reflected in song. Here, we manipulated the genetic make-up of canaries (Serinus canaria) via inbreeding, and studied its effects upon song output, complexity, phonetics and, for the first time, song learning. To this end, we created weight-matched inbred and outbred pairs of male fledglings, which were subsequently exposed to the same tutor male during song learning. Inbreeding strongly affected syllable phonetics, but there were little or no effects on other song features. Nonetheless, females discriminated among inbred and outbred males, as they produced heavier clutches when mated with an outbred male. Our study highlights the importance of song phonetics, which has hitherto often been overlooked.

At the end of the month I will be embarking on a new career as a biology teacher. In a bid to try and get my students engaged in science outside of the class room and to help them see the bigger picture of science, i.e. biology is not just the curriculum you learn in school, I have put together a list of websites, youtube channels and podcasts that will broaden their horizons. I realised that this list might be of interest to other people who are teachers or just interested in science in general and would appreciate a signpost to some good content.

This list is more biology focused but it does include general science, as well as more pop culture stuff like Radiolab and Stuff You Should Know. I'm going to try and impress upon my students the ease of podcasts, they're a great tool for enjoying learning and can be listened to while on route to school, going for a run or cleaning your room (all situations in which I listen to them). I know that not every student will read watch or listen to my suggestions but if I can hook a few in then I'll have done my job!

Things to listen to or watch outside of class
 
To read:
 
Websites
IFL Science - http://www.iflscience.com/
The Conversation - http://theconversation.com/uk
BBC science - http://www.bbc.co.uk/news/science_and_environment
Guardian science - https://www.theguardian.com/uk/environment
Real Clear Science - http://www.realclearscience.com/
 
Blogs
Carl Zimmer - http://carlzimmer.com/
Ed Yong (Nat Geo) - http://phenomena.nationalgeographic.com/blog/not-exactly-rocket-science/
WIRED - http://www.wired.com/tag/science-blogs-2/
popsci.com - http://www.popsci.com/blog-network
Nature’s top blog list - http://www.nature.com/news/2006/060703/multimedia/50_science_blogs.html
 
To watch:
 
TED talks - https://www.ted.com/talks
TED science - https://www.youtube.com/user/TEDtalksDirector
Crash Course - https://www.youtube.com/user/crashcourse
Interactive Biology - https://www.youtube.com/user/InteractiveBiology/
Armando Hasudungan - https://www.youtube.com/user/armandohasudungan
Animal Wonders - https://www.youtube.com/user/Anmlwndrs
Bozeman Biology - https://www.youtube.com/user/bozemanbiology
The Brain Scoop - https://www.youtube.com/user/thebrainscoop
Gross Science - https://www.youtube.com/user/grossscienceshow
Veritasium - https://www.youtube.com/user/1veritasium
 
To listen: (all available on itunes and overcast or directly downloadable)
 
The Infinite Monkey Cage - http://www.bbc.co.uk/programmes/b00snr0w/episodes/downloads
60-second science - http://www.scientificamerican.com/podcast/60-second-science/
Science for the people - http://www.scienceforthepeople.ca/
Guardian Science Weekly - https://www.theguardian.com/science/series/science
The Story Collider - http://www.storycollider.org/
The Naked Scientists - http://www.thenakedscientists.com/HTML/podcasts/naked-scientists/
Nature Podcasts - http://www.nature.com/nature/podcast/
 
Not always science but just great:
Radiolab - http://www.radiolab.org/
Stuff You Should Know - http://www.stuffyoushouldknow.com/podcasts/

I’ve just returned from a fun but fairly hectic trip to the Kalahari. This chance came about because there is a new PhD student starting on the pied babblers but no one was available to train her. So, on a plane I hopped and met up with Amanda Bourne. She’s going to be looking at climate effects on the babblers and be part of the Hot Birds Project. Her work is going to be a mix of: physiology, trying to understand the metabolic costs; behavioural, working out if temperature impacts on social and group cohesive behaviours – trying to see if sociality may act as a buffer to high temperatures; and investigating cumulative impacts of high temperature on groups and individuals. All this is really cool, interesting, and (pardon the pun) hot stuff. She is following on from other hot birds work at the Kuruman River Reserve: van de Ven et al. 2016 found that hornbills can regulate blood flow to their beaks to regulate their temperature without evaporative heat loss; du Plessis et al. 2012 found that increasing temperature caused a decrease in the foraging success of pied babblers, with birds displaying heat dissipation behaviour while foraging. She’ll also be able to build on some recent babbler work by Lizzie Wiley who found that adults provisioned nestlings much less on hot days, resulting in decreased nestling growth (Wiley & Ridley 2016).
 
So why was I there? Well the babblers are a bird with lots of complex behaviours, fairly defined territories and the project has specific protocols to maintain consistent data collection over its 13 year history. The privilege fell to me to basically walk around and look at birds for 10 days solid, life is so hard! But in all seriousness, the study population consists of wild birds who have been habituated to close human presence and without knowing how to act around them it is possible to dehabituate them very quickly and see your PhD data quickly fly away. I was also able to help Amanda figure out potential research questions and experiments that she wouldn’t have been able to think of without seeing how they behave.
 
Before heading off I was anticipating a fairly dull period in the field: its winter, they’re hungry and so they just forage and fly about between the distant patches of low density prey. How wrong I was. This has been a very odd year in the Kalahari, late summer rain in April and a mild winter led to a bumper abundance of food. When food is not a problem the babblers, and all of the other Kalahari animals for that matter, get it on and babies are the result. We arrived to find multiple groups with fledglings, and so the veldt was alive with the begging of babblers – music to my ears. Following these groups of babblers where the scimitar bills taking advantage of babbler sentinels and the ubiquitous drongos. We found groups like Centaurus (pictured below) incubating and even observed some egg eating in a group with females who were competing for reproduction. Whilst other groups were having large aerial battles with their neighbours. Amanda was privileged to observe a dispersal event, the dominant female of Vivaldi was fed up with her light weight male and decided to fly across to join the much heavier male of neighbouring group Noleg, even though at one point she flew back to join her old group for a fight against another group before quickly remembering that she’d left.
 
Whilst looking for groups, and teaching Amanda the babbler whistle (an ululating call to get the birds to fly to you) and group territories, we came across wild groups and individuals who had dispersed from the study population (one may have last been seen in the population in 2004!! – although confirmation is still needed). One of these wild groups was right in the middle of the reserve and feeding a nest, so they’ve been named (Martu- pronounced Mardu – after the aboriginal people of the Western Deserts of Australia) and habituation may start in September when Amanda gets back. 

Amanda’s boyfriend, plant biologist and restoration ecologist extraordinaire, Todd Erickson also came along. He was able to use my camera a lot more than I was, and many of the pictures on the blog post were taken by him. Todd’s botanical leanings allowed me to see the veldt in a new way, paying attention to the small succulents, grasses and flowers that had flourished because of the late rains. The Kalahari was filled with colour, majestic in its flora. This colour had been included in the babbler nests, with many of them decorated with the lovely yellow flowers that littered the landscape. Todd’s insights about how dunes actually hold water better than the slacks, meaning that larger trees and shrubs can grow there, blew my mind and made me look at the landscape in a completely new way. This is why I love science, there are so many disciplines and you can always learn something new that changes your world view.
 
I’ve written mostly about the babblers, and that’s because they are awesome, but there are many other projects at the KRR. There is the over 20 year study of meerkats, who have had a terrible year: prior to the late rains it had been a drought and their groups had been decimated by the combined disasters of no recruitment and TB, but they had started to breed in the winter. The Cape Ground Squirrel Project, started by my friend Jamie Samson, is still going strong and again they have had loads of strange winter pups. And for those of you who want to fly to South Africa, travel for hours to the remote Kalahari and then spend most of your time indoors there are always the molerats to work on. That might sound a bit negative but I like being outside and observing animals behaving in their natural habitat and the idea of spending all day under florescent lights (something you can do in an office) in a building that smells of pee (something you get in public toilets) isn’t something that appeals to me. The other cool birds that are studied at the KRR are the hornbills (mentioned above) and the drongos – who spend their time either stealing food from other animals with their vocal mimicry, catching flying insects with ease using their aerial acrobatics or just pissing off large raptors by bomb diving them.

It was very special to go back to the Kalahari, a place that I have spent a lot of time. Seeing the babblers again, watching them play in shepherd’s trees, feed their fledglings or just have them hop on my feet as I weighed them was very special. I also found out that part of my hippocampus is forever engraved with a map of the reserve: I could still walk straight to ladders hidden behind bushes, find trees that had been used as nests in the past and always point to Whiskers Crossing. Part of me will always be in the Kalahari, and no view will ever be as beautiful as the sun setting over the dunes or a time as peaceful as dawn in the veldt.