IS: Who are you and what do you do?

TL: My name is Tanya Latty and I am a lecturer/researcher in the Faculty of Agriculture and Environment at Sydney Uni. My research is focused mostly on collective and group behaviours in social insects like ants and bees, although I am also interested in integrated pest management and the management of pollinators in agricultural systems.

 IS: How did you end up researching social insects?

TL: I did my PhD on bark beetles which attack and kill live trees. The only way they can do this without being killed by the tree’s resin defences is to attack in enormous groups. Working with them got me really interested in understanding how insect groups are coordinated.

 IS: What is your favourite social insect and why?

TL: That’s a hard one- there are so many to choose from! Today, I’d have to say bull ants (Myrmecia sp) because they are so over-the-top aggressive. I love the way they charge at you as if they haven’t realized how much smaller they are- that, or they don’t care. Research-wise, my current favourites are Australian meat ants (Iridomyrmex purpureus). They build efficient transportation networks, farm hemipterans, and have beautiful nest mounds decorated with sticks and rocks.

IS: What is the best moment/discovery in your research so far? What made it so memorable?

 TL: My favourite moment has little to do with my actual research. I was finishing my first day of field work in the Canadian Rocky Mountains in an isolated patch of forest along a fire road. Just as I reached my car, I turned around in time to see an ENORMOUS cougar follow me out of the bush! Cougars are elusive and you really only see them if they are stalking you, which this one clearly was. I jumped in my car and watched in terrified awe as this pony-sized cat walked around my car a few times before getting bored and wandering back into the forest to stalk some other hapless PhD student. It was an amazing moment because almost no one ever sees cougars in the wild. I felt lucky because a) I hadn’t been eaten but also because b) I had a job that let me spend the whole summer in one of the most wild and beautiful places on earth.

 IS: If teaching is part of your work, what courses do you teach? Has your work on social insects helped to shape your teaching?

TL: I teach Introduction to Entomology, Integrated Pest Management, and Insect Taxonomy and Systematics. I use a lot of social insect examples in all three courses.

IS: What is the last book you read? Would you recommend it? Why or why not?

TL: The last book I read was ‘The Martian’. I loved it because all the heroes are scientists. I’m currently re-reading ‘American Gods’ by Neil Gaimen. It’s awesome because it’s Neil Gaimen.

IS: Did any one book have a major influence in shaping your career? What was the book and how did it affect you?

TL: I went through a phase of wanting to be an astronaut, so I was in love with the book ‘Moon Shot: The Inside Story of America’s Race to the Moon’ written by Apollo astronaut Alan Shepherd. It actually had the opposite effect as I worked out the mortality rate of astronauts and decided it was too risky a career choice.

IS: Outside of science, what are your favourite activities, hobbies or sports?

TL: I enjoy bushwalking, minding (and typically killing) plants in my veggie patch and hanging out with my family.

IS: How do you keep going when things get tough?

TL: I go and play with my three year old daughter. She thinks I’m a super hero.

IS: If you were on an island and could only bring three things, what would you bring? Why?

TL: Food, a desalinisation device and a fully fuelled/equipped yacht. Because my goal would be to get off that island as fast as possible.

 IS: Who do you think has had the greatest influence on your science career?

TL: My mum and dad. My mum let me keep all sorts of creepy crawly things in the house, even though she was terrified of them and they had an annoying tendency to escape. They are both scientists so I was very lucky to be exposed to lots of interesting things from a very early age.

 IS: What advice would you give to a young person hoping to be a social insect researcher in the future?

 TL: That’s a tricky question. It’s a tough job market at the moment. I know firsthand how discouraging it can be when you are chasing down funding/jobs and worrying about whether or not you can continue as a researcher. That part sucks. But the flip side is that we get to study the things that we love and we get to surround ourselves with lovely, nerdy, passionate people who share our interests. It is not a guaranteed job, it’s not necessarily a stable job, but it IS a great job. I’d tell young researchers to stay positive and enjoy the ride. Even if it doesn’t work out in the end, you will have enjoyed yourself doing a job you loved- few people get that opportunity.

 

Highlighting the article by da Silva, Stevens and Schwarz in Insectes Sociaux

Written by Insectes Sociaux Associate Editor Miriam Richards

My favourite social bee is generally the one that I am writing a paper on, which at the moment is the Eastern Carpenter Bee, Xylocopa virginica. The more we study this bee, the more complex and interesting its social behaviour gets, which is mildly ironic, because recently a reviewer suggested that despite complicated behavioural interactions among co-nesting females, these carpenter bees are not “truly social”. The still rather widespread presumption that caste-based eusociality is the only “true” form of sociality certainly influences how we think about social evolution in insects. [1] The recent publication in Insectes Sociaux of a paper entitled “Casteless sociality in an allodapine bee and evolutionary losses of social hierarchies” by da Silva, Stevens and Schwarz (2015), provides a timely reminder of the enormous breadth of social behaviour in bees, which includes both caste-based and casteless forms.

Allodapine bees are the best studied of four tribes in the carpenter bee clade (Xylocopinae), thanks to years of research by Mike Schwarz and his colleagues at Flinders University in Australia.   Allodapine bees exhibit several distinctive characteristics, including progressive provisioning of their offspring, which are raised in chambers excavated in plant stalks and branches. They also exhibit a wide range of colony types, from mostly subsocial species to eusocial, including a highly eusocial species whose morphologically distinct castes represent an independent transition to this form of obligate eusociality (Dew et al., 2012). Da Silva and colleagues studied Braunsapis puangensis nesting at several locations in Fiji (!), collecting nests and examining their contents. These bees live in small groups of up to five females, with the modal group size being one, suggesting that females can nest either solitarily or socially. By comparing the number of brood in a nest to the number of adult females, da Silva et al. estimated the per capita rate of brood production in nests with differing numbers of females. Two main trends emerged. First, social nests almost invariably contain brood whereas solitary nests often do not. This is consistent with a general pattern in allodapine bees in which sociality protects against total brood loss. Second, in social nests with brood, the main predictor of per capita brood productivity was the length of the nest cavity, with per capita brood productivity declining as group size increased. This is a surprising conclusion because in previous studies of allodapines, Schwarz’s group has found a positive relationship between group size and per capita productivity. The study thus provides “a clear benefit to social nesting in terms of preventing brood loss”, but no advantage (indeed, a detriment) when group size increases above two females.

Perhaps the most interesting finding in this paper is that referred to in the title: multi-female groups comprise casteless societies. In most social insects, the familiar queen and worker castes exhibit a negative association between reproduction and work. An idiosyncracy of social carpenter bees is that the reproductive castes can be based on a positive association between reproduction and work (Hogendoorn and Velthuis, 1999). However, in Braunsapis puangensis, there is no evidence of either type of caste division – co-nesting females are no more different in wing wear (which measures foraging activity) and ovarian development (which measures reproductive potential) than randomly selected pairs of solitary females. Although Schwarz’s group prefer the term “casteless sociality”, the more traditional term “communal” would also appear to be an apt descriptor of colony social organization in B. puangensis. Phylogenetically, B. puangensis seems to represent an evolutionary transition from a hierarchical, caste-based form of sociality to an egalitarian, casteless form of sociality. Although it was once predicted that communal and eusocial behaviour were mutually exclusive and not to be found in the same clade, but it would appear that B. puangensis provides us with a rare piece of evidence refuting this hypothesis.

How rare is communal behaviour in bees, and is the almost complete absence of communal behaviour in eusocial lineages real? It’s difficult to tell, because current approaches emphasize caste-biased sociality, relegating other forms to the “not truly social” category. For instance, in a recent phylogenetic study investigating evolutionary transitions between solitary and social behaviour in halictine bees, communal species were classified as solitary while species with caste-based societies were classified as social (Gibbs et al., 2012). [2] In another recent contribution to Insectes Sociaux, Dew, Tierney and Schwarz (2015) emphasize that our ability to identify egalitarian, casteless societies in bees depends on how we define communal, egalitarian behaviour and the observational methods used to distinguish it from hierarchical forms of colony social organization. I would not be surprised to find out that in bees, at least, casteless and other types of non-eusocial societies, are a lot more common than we currently think.

Author’s footnotes:

[1] Of course, I disagreed with the reviewer and included the word “social” in the title – not once, but twice! (Richards, 2011)

[2] Some of the authors of this paper have been forced to endure considerable haranguing from me about behavioural differences between solitary and communal bees, which they did with great good humour.

References

da Silva, C.R.B., Stevens, M.I., and Schwarz, M.P. 2015. Casteless sociality in an allodapine bee and evolutionary losses of social hierarchies. Insectes Soc. http://link.springer.com/10.1007/s00040-015-0436-0

Dew, R.M., Rehan, S.M., Tierney, S.M., Chenoweth, L.B., and Schwarz, M.P. 2012. A single origin of large colony size in allodapine bees suggests a threshold event among 50 million years of evolutionary tinkering. Insectes Soc. 59: 207–214

Dew, R.M., Tierney, S.M., and Schwarz, M.P. 2015. Social evolution and casteless societies: needs for new terminology and a new evolutionary focus. Insectes Soc.

Gibbs, J., Brady, S.G., Kanda, K., and Danforth, B.N. 2012. Phylogeny of halictine bees supports a shared origin of eusociality for Halictus and Lasioglossum (Apoidea: Anthophila: Halictidae). Mol. Phylogenet. Evol. 65: 926–939

Hogendoorn, K., and Velthuis, H.H.W. 1999. Task allocation and reproductive skew in social mass provisioning carpenter bees in relation to age and size. Insectes Soc. 46: 198–207

Richards, M.H. 2011. Colony social organisation and alternative social strategies in the eastern carpenter bee, Xylocopa virginica. J. Insect Behav. 24: 399–411

da Silva, C.R.B., Stevens, M.I., and Schwarz, M.P. 2015. Casteless sociality in an allodapine bee and evolutionary losses of social hierarchies. Insectes Soc.