So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

Genetics and analysis of quantitative traits

MUCKE aims to mine a large volume of images, to structure them conceptually and to use this conceptual structuring in order to improve large-scale image retrieval. The last decade witnessed important progress concerning low-level image representations. However, there are a number problems which need to be solved in order to unleash the full potential of image mining in applications. The central problem with low-level representations is the mismatch between them and the human interpretation of image content. This problem can be instantiated, for instance, by the incapability of existing descriptors to capture spatial relationships between the concepts represented or by their incapability to convey an explanation of why two images are similar in a content-based image retrieval framework. We start by assessing existing local descriptors for image classification and by proposing to use co-occurrence matrices to better capture spatial relationships in images. The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images. Consequently, we introduce methods which tackle these two problems and compare results to state of the art methods. Note: some aspects of this deliverable are withheld at this time as they are pending review. Please contact the authors for a preview.

http://ieeexplore.ieee.org/iel2/4524/12820/00592460.pdf

Image Processing

In his introduction to this detailed survey of knowledge of insect societies, the author points out that research on insect sociology has proceeded in three phases, the natural history phase, the physiological phase and the population-biology phase. Advances in the first two phases have permitted embarkation in the third phase on a more rigorous theory of social evolution based on population genetics and writing this book, the author wished to relate the three phases of research on insects and to express insect sociology as population biology. A glossary of terms, a considerable bibliography and a general index are included. Other CABI sites 

The Insect Societies

Recent studies in the field of behavioural ecology have revealed intriguing variation in behaviour within single populations. Increasing evidence suggests that individual animals differ in their average level of behaviour displayed across a range of contexts (animal 'personality'), and in their responsiveness to environmental variation (plasticity), and that these phenomena can be considered complementary aspects of the individual phenotype. How should this complex variation be studied? Here, we outline how central ideas in behavioural ecology and quantitative genetics can be combined within a single framework based on the concept of 'behavioural reaction norms'. This integrative approach facilitates analysis of phenomena usually studied separately in terms of personality and plasticity, thereby enhancing understanding of their adaptive nature.

https://www.cell.com/trends/ecology-evolution/pdf/S0169-5347(09)00243-2.pdf

Behavioural reaction norms: animal personality meets individual plasticity

Parental care is a trait that shows tremendous diversity both within and across different animal taxa, and is an important topic in evolutionary biology and behavioural ecology. Parental care forms an integral part of an organism’s reproduction, development, and life-history, and because caring for offspring means that parents have less time, resources, or energy available to search for or attract mates, the evolution of parental care is closely linked with sexual selection. In addition, the evolution of parental care represents an important step in the evolution of sociality as it leads to the formation of family groups, which provides a bridge to more complex forms of social structures. But because parents and offspring share only some of their genes, conflicts emerge in sexually reproducing organisms that shape the evolution of parental care and offspring strategies to demand care. As a consequence, the family also constitutes a model to understand the evolutionary tension between cooperation and conflict. This edited book is: The first comprehensive review of the evolution of parental care for over 20 years Integrates contributions from leading international authors to provide an interdisciplinary synthesis of the field Establishes key concepts and draws on general principles whilst emphasizing a broad taxonomic approach Emphasizes behavioural interactions and the co-evolution of parents and offspring Includes the latest research findings, suggesting avenues for future study Parental care includes a wide variety of traits that enhance offspring development and survival. It is taxonomically widespread and is central to the maintenance of biodiversity through its close association with other phenomena such as sexual selection, life-history evolution, sex allocation, sociality, cooperation and conflict, growth and development, genetic architecture, and phenotypic plasticity. This novel book provides a fresh perspective on the study of the evolution of parental care based on contributions from some of the top researchers in the field. It provides evidence that the dynamic nature of family interactions, and particularly the potential for co-evolution among family members, has contributed to the great diversity of forms of parental care and life-histories across as well as within taxa. The Evolution of Parental Care aims to stimulate students and researchers alike to pursue exciting new directions in this fascinating and important area of behavioural and evolutionary biology. It will be of relevance and use to those working in the fields of animal behaviour, ecology, evolution, and genetics, as well as related disciplines such as psychology and sociology. Readership: Suitable for researchers and students working in the fields of animal behaviour, ecology, evolution, and genetics, as well as related disciplines such as psychology and sociology.

The evolution of parental care

Rich and ephemeral resources, such as carrion, are a source of intense interspecific competition among animal scavengers and microbial decomposers. Janzen [Janzen DH (1977) Am Nat 111:691–713] hypothesized that microbes should be selected to defend such resources by rendering them unpalatable or toxic to animals, and that animals should evolve counterstrategies of avoidance or detoxification. Despite the ubiquity of animal-microbe competition, there are few tests of Janzen's hypothesis, in particular with respect to antimicrobial strategies in animals. Here, we use the burying beetle Nicrophorus vespilloides, a species that obligately breeds on carcasses of small vertebrates, to investigate the role of parental care and avoidance as antimicrobial strategies. We manipulated competition between beetle larvae and microbes by providing beetles with either fresh carcasses or old ones that had reached advanced putrefaction. We found evidence for a strong detrimental effect of microbial competition on beetle reproductive success and larval growth. We also found that parental care can largely compensate for these negative effects, and that when given a choice between old and fresh carcasses, parents tended to choose to rear their broods on the latter. We conclude that parental care and carcass avoidance can function as antimicrobial strategies in this species. Our findings extend the range of behavioral counterstrategies used by animals during competition with microbes, and generalize the work of Janzen to include competition between microbes and insects that rely on carrion as an obligate resource for breeding and not just as an opportunistic meal.

https://www.pnas.org/content/pnas/105/46/17890.full.pdf

Antimicrobial strategies in burying beetles breeding on carrion

Species where, from birth, the offspring feed themselves in addition to begging for food from the parents can be described as 'partially begging'. Such species provide a unique opportunity to examine the evolution of offspring begging from non-signalling offspring foraging strategies. We used the partially begging burying beetle Nicrophorus vespilloides to test specific hypotheses concerning the coexistence of begging and self-feeding. We first tested whether the cessation of larval begging coincided with an increase in the efficiency of self-feeding. As predicted, begging ceased when the efficiency of self-feeding reached the point where the larvae grew just as well without as with access to food provided by the parent. We next tested whether the transition to nutritional independence was under parental or offspring control. The parent did not change its behaviour towards the larvae over time, while the larvae changed their behaviour by reducing the time spent begging in the presence of the parent. Food allocation during the transition to nutritional independence was therefore under offspring control. Our results on partial begging provide a starting point for new theoretical models for the origin of begging. We suggest that these should be constructed as scramble-competition models because the offspring control food allocation.

/pdf/partial-begging-an-empirical-model-for-the-early-evolution-2rvfuhor2m.pdf

Partial begging: an empirical model for the early evolution of offspring signalling

How do caring parents respond to mate loss? Differential response by males and females

Very few studies have examined parent-offspring interactions from a quantitative genetic perspective. We used a cross-fostering design and measured genetic correlations and components of social selection arising from two parental and two offspring behaviors in the burying beetle Nicrophorus vespilloides. Genetic correlations were assessed by examining behavior of relatives independent of common social influences. We found positive genetic correlations between all pairs of behaviors, including between parent and offspring behaviors. Patterns of selection were assessed by standardized performance and selection gradients. Parental provisioning had positive effects on offspring performance and fitness, while remaining near the larvae without feeding them had negative effects. Begging had positive effects on offspring performance and fitness, while increased competition among siblings had negative effects. Coadaptations between parenting and offspring behavior appear to be maintained by genetic correlations and functional trade-offs; parents that feed their offspring more also spend more time in the area where they can forage for themselves. Families with high levels of begging have high levels of sibling competition. Integrating information from genetics and selection thus provides a general explanation for why variation persists in seemingly beneficial traits expressed in parent-offspring interactions and illustrates why it is important to measure functionally related suites of behaviors.

https://www.jstor.org/stable/10.1086/421444

Per T. Smiseth

Papers

The evolution of parental care

Antimicrobial strategies in burying beetles breeding on carrion

Partial begging: an empirical model for the early evolution of offspring signalling

How do caring parents respond to mate loss? Differential response by males and females

Selection, inheritance, and the evolution of parent-offspring interactions