I\u2019m a Professor of Biology at the School of Biology, University of St Andrews, Scotland.<\/p>\n
I work on Darwinian adaptation. Natural selection explains the appearance of design in the living world, but at what level is this design expected to manifest \u2013 gene, individual, society \u2013 and what is its function? Social evolution provides a window on this problem, by pitting the interests of genes, individuals and societies against each other. I develop general theory on the topics of inclusive fitness and multilevel selection, and also tailor general theory to the biology of particular species to facilitate empirical testing. I work on a wide range of biological systems, including viruses, bacteria, protozoa, crustaceans, insects, arachnids, fish, mice and humans.<\/p>\n
Lab website: https:\/\/gardner.wp.st-andrews.ac.uk\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":" I work on Darwinian adaptation. Natural selection explains the appearance of design in the living world, but at what level is this design expected to manifest \u2013 gene, individual, society \u2013 and what is its function?<\/p>\n","protected":false},"author":62,"featured_media":16,"parent":0,"menu_order":0,"template":"","class_list":["post-159","research_group","type-research_group","status-publish","has-post-thumbnail","hentry"],"jetpack_sharing_enabled":true,"group_members":"Andy Gardner<\/h2>\r\n<\/header>\r\n
\r\n\r\nE: andy.gardner@st-andrews.ac.uk<\/a>\r\nT: +44 (0) 1334 463 385\r\nF: +44 (0) 1334 463 366\r\n\r\n \r\n\r\n<\/div>","publications":"[publications flag='individual' code='ag243' dois='1' max='10' categorise='1']","research_projects":"I\u00a0work on a range of topics within \u2013 and beyond \u2013 the field of social evolution. Mostly, I focus on Darwinian adaptation: see \u201cAdaptation as organism design\u201d<\/a> (Gardner 2009, Biol Lett<\/em>) for a brief\u00a0\u2018manifesto\u2019. Here, I outline some recent research themes.\r\n\r\n \r\nKin selection and inclusive fitness<\/h3>\r\nNatural selection may operate both directly \u2013 via the impact that the individual has on her own fitness \u2013 and also indirectly \u2013 via the impact that she has on the fitness of her genetic relatives, i.e. \u201ckin selection\u201d. As a consequence of natural selection, the individual appears adapted to maximize the overall reproductive success of all her social partners, each increment or decrement being weighted by her genetic relatedness to that individual, i.e. her \u201cinclusive fitness\u201d. I develop theory on the topics of kin selection and inclusive fitness, and apply this theory to understand the evolution of social behaviours from microbes to insects to humans.\r\n\r\nFind out more:\r\n\r\n\u201cThe genetical theory of kin selection\u201d<\/a>\u00a0(Gardner et al 2011, J Evol Biol)\r\n\r\n\u201cThe meaning of death: evolution and ecology of apoptosis in protozoan parasites\u201d<\/a> (Reece et al 2011, PLoS Pathogens)\r\n\r\n\u201cSpite and virulence in the bacterium Pseudomonas aeruginosa<\/em>\u201c<\/a> (Inglis et al 2009, PNAS)\r\n\r\n\u201cAdaptation and the evolution of parasite virulence in a connected world\u201d<\/a> (Wild et al 2009, Nature)\r\n\r\n \r\n
Group selection and group adaptation<\/h3>\r\nNatural selection may instead be conceptualised as operating within and between social groups, which provides an alternative \u2013 but equivalent \u2013 approach to understanding social adaptations. I develop theory on group selection, with a particular focus on the complexities associated with class-structured populations. I also investigate the conditions under which group selection may give rise to adaptation at the level of the social group, i.e. a \u201csuperorganism\u201d. My work has highlighted that, whilst group selection is ubiquitous in nature, group adaptation is rare, on account of within-group selection acting to erode adaptive integrity at the group level.\r\n\r\nFind out more:\r\n\r\n\u201cGroup selection versus group adaptation\u201d<\/a>\u00a0(Gardner 2015, Nature)\r\n\r\n\u201cThe genetical theory of multilevel\u00a0selection\u201d<\/a>\u00a0(Gardner 2015, J Evol Biol)\r\n\r\n\u201cAdaptation of individuals and groups\u201d<\/a>\u00a0(Gardner 2013, In: From Groups To Individuals, MIT Press)\r\n\r\n\u201cCapturing the superorganism: a formal theory of group adaptation\u201d<\/a>\u00a0(Gardner & Grafen 2009,\u00a0J Evol Biol)\r\n\r\n \r\n
Selfish genes and intragenomic conflict<\/h3>\r\nI also study adaptation and conflicts of interest at the level of individual genes. These too become adapted, as a result of selection, to maximise their inclusive fitness, leading to the existence of altruistic and spiteful \u2013 and not just selfish \u2013 genes. I am particularly interested in understanding intragenomic conflicts of interest that arise in the absence of selection within the individual genome, such as in relation to genomic imprinting and greenbeard genes.\r\n\r\nFind out more:\r\n\r\n\u201cThe meaning of intragenomic conflict\u201d<\/a> (Gardner & \u00dabeda 2017, Nature Ecol Evol)\r\n\r\n\u201cIntrafamily and intragenomic conflicts in human warfare\u201d<\/a>\u00a0(Micheletti et al 2017, Proc B)\r\n\r\n\u201cA formal theory of the selfish gene\u201d<\/a>\u00a0(Gardner & Welch\u00a02011,\u00a0J Evol Biol)\r\n\r\n\u201cGreenbeards\u201d<\/a>\u00a0(Gardner & West 2010, Evolution)\r\n\r\n \r\n
Haplodiploidy and eusociality<\/h3>\r\nPerhaps the most famous kin selection hypothesis is that haplodiploid genetics has promoted the evolution of altruistic sib rearing in the social hymenoptera (ants, bees & wasps), on account of the inflated genetic relatedness between sisters. However, this hypothesis does not really make sense, either theoretically or empirically. I have developed theory to understand the impact that haplodiploidy has had on the evolution of eusociality via inflated sororal relatedness, showing that its effect is typically weak and that it may even be inhibitory. And I\u2019ve investigated the role for haplodiploidy to have driven sex-biased helping in the social hymenoptera. Finally, I\u2019ve suggested that haplodiploidy may have preadapted certain taxa to eusociality by enabling them to easily adjust sex allocation towards the more helpful sex, and shown that ease of sex-ratio adjustment is a major determinant of which sex or sexes help in arthropod societies.\r\n\r\nFind out more:\r\n\r\n\u201cThe ecology of sex explains patterns of helping in arthropod societies\u201d<\/a> (Davies et al 2016, Ecol Lett)\r\n\r\n\u201cHaplodiploidy, sex-ratio adjustment and eusociality\u201d<\/a>\u00a0(Gardner & Ross 2013, Am Nat)\r\n\r\n\u201cEcology, not the genetics of sex determination, determines who helps in eusocial populations\u201d<\/a>\u00a0(Ross et al 2013, Curr Biol)\r\n\r\n\u201cHaplodiploidy and the evolution of eusociality: split sex ratios\u201d<\/a>\u00a0(Gardner et al\u00a02012, Am Nat)\r\n\r\n \r\n
Kin selection and sexual selection<\/h3>\r\nDarwin\u2019s initial musings on kin selection and sexual selection first appeared in the Origin of Species<\/em>, and have developed into two very large \u2014 but curiously disconnected \u2014 literatures. I\u2019ve reviewed the broad connections between the two theories, investigated how kin selection may put the brakes on (and foment intragenomic conflicts in relation to) harmful sexual conflict in viscous populations, and shown the logical connections between the greenbeard and sexy-son effects.\r\n\r\nFind out more:\r\n\r\n\u201cThe relation between R. A. Fisher\u2019s sexy-son hypothesis and W. D. Hamilton\u2019s greenbeard effect\u201d<\/a>\u00a0(Faria et al 2018, Evol Lett)\r\n\r\n\u201cSexual selection modulates genetic conflicts and patterns of genomic imprinting\u201d<\/a> (Faria et al 2017, Evolution)\r\n\r\n\u201cSex-biased dispersal, kin selection and the evolution of sexual conflict\u201d<\/a> (Faria et al 2015, J Evol Biol)\r\n\r\n\u201cThe sociobiology of sex: inclusive fitness consequences of inter-sexual interactions\u201d<\/a>\u00a0(Pizzari & Gardner 2012, Phil Trans B)\r\n\r\n \r\n
Evolution of reproductive systems<\/h3>\r\nWhilst much of social evolution theory is concerned with understanding the impact of mode of reproduction upon the evolution of social behaviour, I have also been interested in understanding how social evolution may drive the evolution of reproductive systems themselves. I\u2019ve considered how population demography and mode of sex determination may interact in driving the evolution of haplodiploidy and paternal genome elimination. I\u2019ve also investigated the role for sibling conflict to drive the evolution of parental care, in the form of food provisioning, and whether haplodiploidy promotes or inhibits the evolution of maternal care, relative to diploid inheritance.\r\n\r\nFind out more:\r\n\r\n\u201cHow to make a haploid male\u201d<\/a>\u00a0(Ross et al 2019, Evol Lett)\r\n\r\n\u201cMating ecology explains patterns of genome elimination\u201d<\/a>\u00a0(Gardner & Ross\u00a02014, Ecol Lett)\r\n\r\n\u201cEvolution of maternal care in diploid and haplodiploid populations\u201d<\/a>\u00a0(Gardner 2012,\u00a0J Evol Biol)\r\n\r\n\u201cEvolution of parental care driven by mutual reinforcement of parental food provisioning and sibling competition\u201d<\/a>\u00a0(Gardner & Smiseth 2011, Proc R Soc Lond B)\r\n\r\n \r\n
Sex allocation<\/h3>\r\nThe proportional investment into males versus females is perhaps the classic social evolutionary trait. I\u2019ve developed theory on this topic, in particular focusing on the demographic drivers of female-biased sex ratios and, for example, confirming that kin selection may be responsible for the extraordinary sex ratios observed in social spiders. I\u2019ve also investigated facultative sex ratio adjustment in response to strain diversity in malaria infections, with an interplay of theoretical and experimental research, which has demonstrated that malaria parasites are able to discriminate their kin.\r\n\r\nFind out more:\r\n\r\n\u201cSimultaneous failure of two sex-allocation invariants: implications for sex-ratio variation within and between populations\u201d<\/a>\u00a0(Rodrigues & Gardner 2015, Proc B)\r\n\r\n\u201cDynamics of sex ratio and female unmatedness under haplodiploidy\u201d<\/a>\u00a0(Gardner 2014,\u00a0Ecol &\u00a0Evol)\r\n\r\n\u201cBudding dispersal and the sex ratio\u201d<\/a>\u00a0(Gardner et al 2009,\u00a0J Evol Biol)\r\n\r\n\u201cSex ratio adjustment and kin discrimination in malaria parasites\u201d<\/a>\u00a0(Reece et al\u00a02008, Nature)\r\n\r\n \r\n
Social evolution in viscous populations<\/h3>\r\nOne way for genetic relatedness to occur between social partners is if individuals tend not to disperse far during their lifetime, such that their neighbours tend to be genealogical kin. This has led to the expectation that indiscriminate cooperation will tend to be promoted by limited dispersal. However, in the simplest models of inelastic population structure, the cooperation-promoting effect of increased relatedness is exactly cancelled out by a cooperation-inhibiting effect of intensified local competition for resources. I develop theory to understand the demographic, genetic and cognitive modulators of cooperation in viscous populations, including the cooperation-promoting potential of sex-biased dispersal, dispersal-dependent social behaviour and weird ploidy.\r\n\r\nFind out more:\r\n\r\n\u201cEvolution of helping and harming in heterogeneous groups\u201d<\/a>\u00a0(Rodrigues & Gardner 2013, Evolution)\r\n\r\n\u201cA general ploidy model for the evolution of helping in viscous populations\u201d<\/a>\u00a0(Yeh & Gardner 2012,\u00a0J Theor\u00a0Biol)\r\n\r\n\u201cSex-biased dispersal of adults mediates the evolution of altruism among juveniles\u201d<\/a>\u00a0(Gardner 2010, J Theor Biol)\r\n\r\n\u201cNice natives and mean migrants: the evolution of dispersal-dependent social behaviour in viscous populations\u201d<\/a>\u00a0(El Mouden & Gardner 2008, J Evol Biol)\r\n\r\n \r\n
Selection and adaptation in other media<\/h3>\r\nOne way to better understand the central Darwinian logic of selection and adaptation is to consider if and how it applies outwith the real-world biological realm. I\u2019ve developed theory of kin selection under the assumption of blending inheritance, confirming that its logic does hold up and that Darwin\u2019s musings on kin selection do make sense even though he didn\u2019t know about genes. And, at the level of whole universes, I\u2019ve used Price\u2019s theorem to formalise hypotheses concerning the apparent fine-tuning of the fundamental constants of nature, including the \u201ccosmological natural selection\u201d and \u201canthropic bias\u201d hypotheses. Much of this work is inevitably a bit tongue-in-cheek.\r\n\r\nFind out more:\r\n\r\n\u201cLife, the universe and everything\u201d<\/a>\u00a0(Gardner 2014, Biol & Philos)\r\n\r\n\u201cCosmological natural selection and the purpose of the universe\u201d<\/a>\u00a0(Gardner & Conlon 2013, Complexity)\r\n\r\n\u201cKin selection under blending inheritance\u201d<\/a>\u00a0(Gardner 2011, J Theor Biol)\r\n\r\n\u201cThe Price equation\u201d<\/a> (Gardner 2008, Curr Biol)","related_theme":[{"related_groups":[159],"related_centre":85,"ID":47,"post_title":"Consequences of Biological and Behavioural Diversity","post_content":"The Centre for Biological Diversity addresses the consequences of biodiversity at the interface between ecology and evolution. The ecological consequences of biodiversity are considered in terms of processes such as pollination biology, niche construction, and invasion biology.<\/span>","post_excerpt":"The Centre for Biological Diversity addresses the consequences of biodiversity at the interface between ecology and evolution. The ecological consequences of biodiversity are considered in terms of processes such as pollination biology, niche construction, and invasion biology.","post_author":"4","post_date":"2022-01-14 20:27:42","post_date_gmt":"2022-01-14 20:27:42","post_status":"publish","comment_status":"closed","ping_status":"closed","post_password":"","post_name":"consequences-of-biological-and-behavioural-diversity","to_ping":"","pinged":"","post_modified":"2022-02-25 14:02:42","post_modified_gmt":"2022-02-25 14:02:42","post_content_filtered":"","post_parent":0,"guid":"https:\/\/biology.st-andrews.ac.uk\/research\/?post_type=research_theme&p=47","menu_order":0,"post_type":"research_theme","post_mime_type":"","comment_count":"0","comments":false,"_thumbnail_id":["133","4","2022-02-25 14:02:33","2022-02-25 14:02:33","","NB4","","inherit","open","closed","","nb4","","","2022-02-25 14:02:33","2022-02-25 14:02:33","","47","https:\/\/biology.st-andrews.ac.uk\/research\/wp-content\/uploads\/sites\/17\/2022\/01\/NB4.jpg","0","attachment","image\/jpeg","0","133"],"id":47}],"related_centre":[{"ID":85,"post_title":"Centre for Biological Diversity","post_content":"The Centre for Biological Diversity (CBD) is an interdisciplinary group of researchers across St\u00a0Andrews focused on the measurement, origin and consequences of biological variation. The Centre's\u00a0objective is to advance scientific understanding of the diversity of life and contribute pro-actively to policy that protects biological diversity.<\/span>\r\n\r\nMain website<\/a>","post_excerpt":"","post_author":"4","post_date":"2022-01-17 16:17:03","post_date_gmt":"2022-01-17 16:17:03","post_status":"publish","comment_status":"closed","ping_status":"closed","post_password":"","post_name":"centre-for-biological-diversity","to_ping":"","pinged":"","post_modified":"2022-09-20 13:32:17","post_modified_gmt":"2022-09-20 12:32:17","post_content_filtered":"","post_parent":0,"guid":"https:\/\/biology.st-andrews.ac.uk\/research\/?post_type=research_centre&p=85","menu_order":0,"post_type":"research_centre","post_mime_type":"","comment_count":"0","comments":false,"id":85}],"contact":"Room 19, Dyers Brae\r\n\r\nSchool of Biology\r\nUniversity of St Andrews\r\nSt Andrews KY16 9TH\r\nScotland\r\n\r\nE: andy.gardner@st-andrews.ac.uk<\/a>\r\nT: +44 (0) 1334 463 385\r\nF: +44 (0) 1334 463 366","_links":{"self":[{"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/research_group\/159","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/research_group"}],"about":[{"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/types\/research_group"}],"author":[{"embeddable":true,"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/users\/62"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/media\/16"}],"wp:attachment":[{"href":"https:\/\/biology.st-andrews.ac.uk\/research\/wp-json\/wp\/v2\/media?parent=159"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}