---
_id: '6435'
abstract:
- lang: eng
  text: "Social insect colonies tend to have numerous members which function together
    like a single organism in such harmony that the term ``super-organism'' is often
    used. In this analogy the reproductive caste is analogous to the primordial germ\r\ncells
    of a metazoan, while the sterile worker caste corresponds to somatic cells. The
    worker castes, like tissues, are\r\nin charge of all functions of a living being,
    besides reproduction. The establishment of new super-organismal units\r\n(i.e.
    new colonies) is accomplished by the co-dependent castes. The term oftentimes
    goes beyond a metaphor. We invoke it when we speak about the metabolic rate, thermoregulation,
    nutrient regulation and gas exchange of a social insect colony. Furthermore, we
    assert that the super-organism has an immune system, and benefits from ``social
    immunity''.\r\n\r\nSocial immunity was first summoned by evolutionary biologists
    to resolve the apparent discrepancy between the expected high frequency of disease
    outbreak amongst numerous, closely related tightly-interacting hosts, living in
    stable and microbially-rich environments, against the exceptionally scarce epidemic
    accounts in natural populations. Social\r\nimmunity comprises a multi-layer assembly
    of behaviours which have evolved to effectively keep the pathogenic enemies of
    a colony at bay. The field of social immunity has drawn interest, as it becomes
    increasingly urgent to stop\r\nthe collapse of pollinator species and curb the
    growth of invasive pests. In the past decade, several mechanisms of\r\nsocial
    immune responses have been dissected, but many more questions remain open.\r\n\r\nI
    present my work in two experimental chapters. In the first, I use invasive garden
    ants (*Lasius neglectus*) to study how pathogen load and its distribution among
    nestmates affect the grooming response of the group. Any given group of ants will
    carry out the same total grooming work, but will direct their grooming effort
    towards individuals\r\ncarrying a relatively higher spore load. Contrary to expectation,
    the highest risk of transmission does not stem from grooming highly contaminated
    ants, but instead, we suggest that the grooming response likely minimizes spore
    loss to the environment, reducing contamination from inadvertent pickup from the
    substrate.\r\n\r\nThe second is a comparative developmental approach. I follow
    black garden ant queens (*Lasius niger*) and their colonies from mating flight,
    through hibernation for a year. Colonies which grow fast from the start, have
    a lower chance of survival through hibernation, and those which survive grow at
    a lower pace later. This is true for colonies of naive\r\nand challenged queens.
    Early pathogen exposure of the queens changes colony dynamics in an unexpected
    way: colonies from exposed queens are more likely to grow slowly and recover in
    numbers only after they survive hibernation.\r\n\r\nIn addition to the two experimental
    chapters, this thesis includes a co-authored published review on organisational\r\nimmunity,
    where we enlist the experimental evidence and theoretical framework on which this
    hypothesis is built,\r\nidentify the caveats and underline how the field is ripe
    to overcome them. In a final chapter, I describe my part in\r\ntwo collaborative
    efforts, one to develop an image-based tracker, and the second to develop a classifier
    for ant\r\nbehaviour."
acknowledged_ssus:
- _id: Bio
- _id: ScienComp
- _id: M-Shop
- _id: LifeSc
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Barbara E
  full_name: Casillas Perez, Barbara E
  id: 351ED2AA-F248-11E8-B48F-1D18A9856A87
  last_name: Casillas Perez
citation:
  ama: Casillas Perez BE. Collective defenses of garden ants against a fungal pathogen.
    2019. doi:<a href="https://doi.org/10.15479/AT:ISTA:6435">10.15479/AT:ISTA:6435</a>
  apa: Casillas Perez, B. E. (2019). <i>Collective defenses of garden ants against
    a fungal pathogen</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:6435">https://doi.org/10.15479/AT:ISTA:6435</a>
  chicago: Casillas Perez, Barbara E. “Collective Defenses of Garden Ants against
    a Fungal Pathogen.” Institute of Science and Technology Austria, 2019. <a href="https://doi.org/10.15479/AT:ISTA:6435">https://doi.org/10.15479/AT:ISTA:6435</a>.
  ieee: B. E. Casillas Perez, “Collective defenses of garden ants against a fungal
    pathogen,” Institute of Science and Technology Austria, 2019.
  ista: Casillas Perez BE. 2019. Collective defenses of garden ants against a fungal
    pathogen. Institute of Science and Technology Austria.
  mla: Casillas Perez, Barbara E. <i>Collective Defenses of Garden Ants against a
    Fungal Pathogen</i>. Institute of Science and Technology Austria, 2019, doi:<a
    href="https://doi.org/10.15479/AT:ISTA:6435">10.15479/AT:ISTA:6435</a>.
  short: B.E. Casillas Perez, Collective Defenses of Garden Ants against a Fungal
    Pathogen, Institute of Science and Technology Austria, 2019.
date_created: 2019-05-13T08:58:35Z
date_published: 2019-05-07T00:00:00Z
date_updated: 2023-09-07T12:57:04Z
day: '07'
ddc:
- '570'
- '006'
- '578'
- '592'
degree_awarded: PhD
department:
- _id: SyCr
doi: 10.15479/AT:ISTA:6435
ec_funded: 1
file:
- access_level: open_access
  checksum: 6daf2d2086111aa8fd3fbc919a3e2833
  content_type: application/pdf
  creator: casillas
  date_created: 2019-05-13T09:16:20Z
  date_updated: 2021-02-11T11:17:15Z
  embargo: 2020-05-08
  file_id: '6438'
  file_name: tesisDoctoradoBC.pdf
  file_size: 3895187
  relation: main_file
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  checksum: 3d221aaff7559a7060230a1ff610594f
  content_type: application/zip
  creator: casillas
  date_created: 2019-05-13T09:16:20Z
  date_updated: 2020-07-14T12:47:30Z
  embargo_to: open_access
  file_id: '6439'
  file_name: tesisDoctoradoBC.zip
  file_size: 7365118
  relation: source_file
file_date_updated: 2021-02-11T11:17:15Z
has_accepted_license: '1'
keyword:
- Social Immunity
- Sanitary care
- Social Insects
- Organisational Immunity
- Colony development
- Multi-target tracking
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
page: '183'
project:
- _id: 2649B4DE-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '771402'
  name: Epidemics in ant societies on a chip
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '1999'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Sylvia M
  full_name: Cremer, Sylvia M
  id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87
  last_name: Cremer
  orcid: 0000-0002-2193-3868
title: Collective defenses of garden ants against a fungal pathogen
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2019'
...