Aarhus University Seal / Aarhus Universitets segl

Former Lab Members

Paolo Ghislandi

I work on the evolution of mating systems, and on understanding how ecological conditions shape alternative male mating strategies. I employ an integrated approach combining field and laboratory studies on behaviour, life history and genetics.

My PhD project is a collaborative research with Dr. Cristina Tuni's lab at LMU Munich.  

Christina Holm

Dietary niche and cooperative foraging strategies in social spider

Background: Social spiders are faced with the challenge of increasing foraging success to fulfil the needs of the group and counter the cost of prey sharing. Hence social spiders are expected to subdue increasingly larger prey to acquire sufficient energy for all consumers, however there is an increased danger of engaging with large prey. To overcome these costs, cooperative foraging should allow for widening of the dietary niche by increasing prey capture rate or prey size range - thereby optimizing foraging for the whole group. It has been proposed that social spiders reside in areas where larger prey are relatively more abundant, suggesting that cooperation in prey capture allows for expansion of the foraging niche to exploit prey of a larger size.

Project: The aim of my study was to explore whether a similar expansion of the dietary niche may apply for a social spider of the Stegodyphus genus. By studying a social (S. dumicola) and subsocial (S. lineatus) species in their native habitat I examined prey availability and prey size preference as factors that may affect their foraging and in particular increase the dietary niche of the social species. Differences between the level of sociality in the way the spiders exploit prey will provide insights into how cooperative societies increase foraging success to reduce resource competition. I found that social spiders have a broader dietary niche compared to the subsocial congener. This suggests that social spiders are able to exploit more of the available prey in habitat by cooperative prey capture. The data also suggest preference among both spider species for certain insect orders over others.​

Blerina Vrenozi

Project background:
The main aim of my postdoctoral study is to understand how sexual selection drives the evolution of alternative male mating strategies. Using the nursery web spider, Pisaura mirabilis, the males of which employ alternative mating strategies such as death feigning and worthless nuptial gifts in the form of an insect prey wrapped in silk offered to females to obtain copulation, we will determine whether behavioural polymorphisms in sexually selected male reproductive traits are stable or plastic, through scoring the frequency of alternative strategies in different populations, and investigate how they co-vary with female mate choice and the intensity of sexual selection.

The intensity of sexual selection will be measured as the natural mating rate of females, which we will determine by genotyping sperm and offspring of field collected females, and the sperm stored in the female spermatheca using microsatellite markers. This requires DNA to be extracted from the females and the young, to run PCR amplifications of the samples, to ship the samples for genotyping, and finally to score the genotypes. With this data, we can examine whether sexual selection intensity predicts the frequencies of male reproductive strategies.  

Cristina Tuni

WHY DO FEMALES MATE WITH MORE THAN ONE MALE?
Recent studies in the field of sexual selection revealed that polyandry (a female mating with more than one male) is far more common than traditionally thought. However, the evolution and maintenance of polyandry remains an intriguing and unresolved topic. I study female polyandry in – predominantly, but not only! – spiders with particular focus on understanding the evolutionary mechanisms driving female mating patterns, in particular whether females gain benefits (material or genetic) by engaging in multiple mating. 

I use i) laboratory mating experiments to study female behaviour and fitness to assess the relationship between genetic and material benefits, showing as for the nuptial feeding spider Pisaura mirabilis that females that gain material donations as food from their mating partners may also gain notable genetic advantages for their offspring; ii) field studies to assess the ecological factors that affect encounter rates among males and females, such as mortality rate, sex ratio and spatial distribution of individuals, which influence the mating strategies adopted by both sexes as shown for the subsocial spiders Stegodyphus lineatus and Stegodyphus bicolor; and finally I conduct iii) paternity analysis using molecular methods to assess patterns of parentage and polyandry in the wild in order to understand whether genetic benefits in the form of inbreeding avoidance apply in naturally inbreeding systems as Stegodyphus lineatus and to understand the post-copulatory mechanisms used by females to control for the fertilization of their eggs to avoid inbreeding, showing that females control sperm stored by multiple males to bias paternity of their offspring in favour of the preferred male.

Dr. Cristina Tuni is an assistant professor at LMU Munich. You can read about her current research here.

Reut Berger-Tal

Costs and Benefits of Inbred Sociality
One of the means to evolution of a cooperative group is by elimination of dispersal from the natal nest, and establishment of a ‘family’ group. Reduced dispersal, however, has implications on the genetic structure and the genetic diversity within the nest, and at the species level. Empirical data on the forces shaping sociality formed by means of limited dispersal is scarce. In my PhD I explore the costs and benefits associated with sociality formed by limited dispersal. I measure the possible costs of inbreeding and the benefits of cooperation by means of kin selection. Social spiders are a well suited system to explore these questions as cooperation was evolved and maintained by means of limited dispersal. I employe complementary methods such as: field observations, controlled lab experiments and chemical profiling, in the social spider Stegodyphus dumicola (Eresidae) by looking at: (i) costs of inbreeding, (ii) benefits of cooperating with kin, (iii) factors that shape dispersal and (iv) measuring mechanisms of possible kin discrimination.

Maria J. Albo

ORIGIN AND EVOLUTION OF NUPTIAL GIFTS IN SPIDERS (PISAURIDAE AND TRECHALEIDAE)

Males offering nuptial gifts are always a target in evolutionary biology. The nuptial gifts are rare in spiders and few species have been described having this special trait. The main objective of our research is to study how was the origin of this character, how it’s maintained and evolves. Our model are the species belonging to Pisauridae and Trechaleidae families; where males wrap an insect prey in silk and offer it to the female during courtship. We focus our studies in how life conditions and selective pressures shape the reproductive behaviors and lead to evolutive changes. Our studies integrate experimental lab work that is supported by field work. 
In collaboration with: Søren Toft (Aarhus University), Cristina Tuni (LMU Munich) ; Gabriele Uhl (Zoology Institute and Museum, Greifswald, Germany); Mariana Trillo y Fernando G. Costa (IIBCE, Uruguay); Luiz-Ernesto Costa-Schmidt and André Klein (Universidad Federal do Rio Grande do Sul, Brasil).

Dr. Maria J. Albo is currently a postdoctoral research fellow at IIBCE (in Spanish).

Michelle Greve

My project explores how sociality, and particularly the concomitant inbreeding displayed in social species, affects the ecophysiological tolerances of Stegodyphus spiders. I will be conducting ecophysiological experiments on social and subsocial Stegodyphus to establish the importance of adaptation vs. phenotypic plasticity in allowing spiders to withstand their environmental extremes. Field and some lab work will be conducted in South Africa in collaboration with Susana Clusella-Trullas (http://www.clusellatrullas.blogspot.com/) at Stellenbosch University. I am also collaborating with Marija Majer in modelling species distributions and using this information to inform on the effects of environment on the origins of sociality.

My background spans a wide variety of organisms and topics, and has mainly dealt with distribution patterns and their determinants at large spatial scales. I started my postgraduate degree at Stellenbosch University in South Africa, where I studied nestedness patterns on Southern Ocean Islands and body size distribution patterns of South African birds, as well as the importance of protected areas for conserving species. I went on to complete my PhD at Aarhus University, where I looked at distribution and diversity patterns of African plants and vegetation types. A description of my past work and publications can be found here: http://pure.au.dk/portal/en/michelle.greve@biology.au.dk

Dr. Michelle Greve is a senior lecturer at the University of Pretoria. You can read about here current research here

Signe Klange

Personalities in spiders

I am studying personalities and task differentiation in social spiders, using the social spider Stegodyphus dumicola and the solitary spider Pisaura mirabilis as a model species.
First, I investigate if spider personalities are variable or consistent throughout individuals’ lifetimes, with special emphasis on the molding stages. Second, I test if differences in metabolic rate among individuals can explain differences in personality. 

Lena Grinsted

The topic of my research is the general evolutionary mechanism involved in the transition to permanent sociality in spiders. Through comparative studies of social and subsocial species from two distinctly different origins of sociality, within Stegodyphus (Eresidae) and Anelosimus (Theridiidae) , I try to identify similar and dissimilar life history traits of social spiders. I am particularly interested in potential task differentiation and the partitioning of reproduction within social spider colonies. 

Dr. Lena Grinsted is a postdoctoral research fellow at the School of Biological Science, Royal Holloway University of London. You can read about her current research here.

Marija Majer

Landscape genetic of an invasive spider undergoing range expansion

The colonial spider Cyrtophora citricola (Araneidae) has a wide geographic distribution in semi-arid, subtropical and tropical areas of Asia, Africa and the Mediterranean basin, and has recently invaded the Americas. Moreover, it is dispersing into new habitats and expanding its range within the Mediterranean. One hypothesis for this range expansion is that C. citricola responds to climatic warming and drying of the Mediterranean region by invading new suitable habitat.
​Additionally, the species may be expanding its range due to the increased area of intensive agriculture. In Israel, colonies in some areas undergo ‘boom & bust’ dynamics, while in other areas they are more stable. Understanding the ecological and genetic parameters that affect population dynamics and result in these population oscillations are vital for predicting the consequences of invasions by C. citricola and their potential threat as agricultural pests
In my postdoc project I investigate genetic and ecological determinants of range-expansion in Cyrtophora citricola using a combination of predictive species distribution modelling and population genetic analyses on samples collected across Israel. 


My project is a collaboration with Trine BildeYael Lubin at Ben-Gurion University of the Negev, and Deborah Smith from Kansas University.

Bram Vanthournout

Male and female biases in offspring production hold an intriguing question for biologists as an equal sex ratio is long considered an evolutionary stable strategy. In line with this, examples of biased sex ratios can be found in nature, though they are relatively rare. One such example is the spider genus Stegodyphus which is characterized by both temporarily (subsocial) and permanently social species. With increasing sociality these species exhibit a more limited male dispersal and consequently elevated levels of inbreeding. Besides these marked differences in relatedness between reproducing individuals a consistent pattern of sex ratio variation is observed with subsocial species producing equal amounts of male and female offspring while social species are highly female biased. This is interesting from a mechanistic point of view as this contradicts the expected equal sex ratio, predicted by a sex chromosome based sex determination. Our aim is to pinpoint the exact reproductive stage  of bias occurrence (sperm production, egg stage,…)  through the use of different molecular techniques such as flow cytometry, next generation sequencing, FISH...

Jessica Barker

Post Doc - 
Aarhus Institute of Advanced
​Studies (AIAS)

  • Cooperation and competition within and between groups
  • Human behaviour
  • Cooperation in insects: sociality and inter-specific mutualism
  • More

Caitlin Stern

Post Doc

  • evolution of sociality
  • evolution of cooperation
  • mathematical modeling of the evolution of behavior
  • More

Julieta Goenaga

Post Doc -
​Aarhus Institute of Advanced Studies (AIAS)

  • ​Sexual selection
  • Evolution of reproductive proteins
  • More