Editing Formica exsecta (section)

==Behavior==

===Sex allocation===
''F. exsecta'' is a [[eusocial]] species, displaying a [[dominance hierarchy]] among its individual colony members. Amongst the narrow-headed ant species, the two different types of colony structure are: [[monogyny]], one queen per colony, and [[Gyne|polygyny]], more than one queen per colony.<ref name=Sundstrom>{{cite journal|last=Sundström|first=Liselotte|author2=Keller, Laurent|author3=Chapuisat, Michel|journal=Evolution|date=1 July 2003|volume=57|issue=7|pages=1552–1561|doi=10.1111/j.0014-3820.2003.tb00363.x|pmid=12940360|url=https://serval.unil.ch/notice/serval:BIB_8AD33563F155|title=Inbreeding and sex-biased gene flow in the ant ''Formica exsecta''|s2cid=22960363|access-date=4 July 2019|archive-date=16 May 2024|archive-url=https://web.archive.org/web/20240516204927/https://serval.unil.ch/en/notice/serval:BIB_8AD33563F155|url-status=live}}</ref> Most commonly, one of these two different types is prevalent within a population. These two types of colonies differ not only in the queen's mating system, but also in the organization of types of offspring and its hierarchy system. For a polygynous colony to thrive, it must adjust its sex allocation practices contingent on the abundance of resources. Colonies produce a greater percentage of male offspring when restraint on resource availability exists, as well as when the colony has a larger number of queens.<ref>{{cite book|last=West|first=Nicholas B. Davies, John R. Krebs, Stuart A.|title=An introduction to behavioural ecology|publisher=Wiley-Blackwell|location=Oxford|isbn=978-1-4051-1416-5|edition=4th|date=2012-04-02}}</ref> The opposite scenario is also found to be true. More female offspring are produced when an abundance of resources exists, as well as when the colony has a smaller number of queens. On average, a colony's sex ratio is estimated to be 5.8% female, or one female for every 17.2 male offspring.<ref>{{cite journal|last=Brown|first=W. D.|author2=Keller, L.|title=Colony sex ratios vary with queen number but not relatedness asymmetry in the ant Formica exsecta|journal=Proceedings of the Royal Society B: Biological Sciences|date=7 September 2000|volume=267|issue=1454|pages=1751–1757|doi=10.1098/rspb.2000.1206|pmid=12233773|pmc=1690740}}</ref> This heavily male offspring-based sex ratio displays an obvious deviation from [[Fisher's principle|Fisher's theory of 1:1 sex ratio]].

In colonies in which the male offspring are favored, workers tend to execute most of the female [[gynes]]. In contrast, colonies where an excess of female gynes is produced, which is more than necessary for the simple act of queen replacement, they are all accepted into the colony to eliminate the possibility of [[parasitism]] by unrelated queens from neighboring populations.<ref>{{cite journal|last=Brown|first=W. D.|author2=Liautard, C.|author3=Keller, L.|title=Sex-ratio dependent execution of queens in polygynous colonies of the ant ''Formica exsecta''|journal=Oecologia|date=January 2003|volume=134|issue=1|pages=12–7|pmid=12647173|doi=10.1007/s00442-002-1072-8|bibcode=2003Oecol.134...12B|s2cid=19403070|url=https://serval.unil.ch/resource/serval:BIB_E94414CC9809.P001/REF.pdf|access-date=2019-12-13|archive-date=2024-05-16|archive-url=https://web.archive.org/web/20240516204846/https://serval.unil.ch/resource/serval:BIB_E94414CC9809.P001/REF.pdf|url-status=live}}</ref>

===Inbreeding===
In monogynous colonies, a significant amount of inbreeding is found. Inbreeding coefficients were found positive for the workers of these colonies. No inbreeding was found between mother queens.  Procreation between related individuals of the colony can be further explained by the queen-male relatedness coefficient of 0.23, found by experiments from [[Liselotte Sundström]].<ref name=Sundstrom /> Male offspring that were reared in an inbred colony tended to be smaller in mass. Gynes reared in inbred colony display no difference in mass compared to those in noninbred colonies. This result reflects a trade-off between the quantity of offspring and their reproductive potential. Gynes' reproductive success is more dependent on their mass than that of a male.<ref>{{cite journal|last=Vitikainen|first=Emma|author2=Haag-Liautard, Cathy|author3=Sundström, Liselotte|journal=Evolution|date=1 July 2011|volume=65|issue=7|pages=2026–2037|doi=10.1111/j.1558-5646.2011.01273.x|pmid=21729057|title=Inbreeding and reproductive investment in the ant ''Formica exsecta''|url=http://doc.rero.ch/record/24833/files/haa_iri.pdf|doi-access=free|access-date=13 December 2019|archive-date=21 January 2022|archive-url=https://web.archive.org/web/20220121214757/http://doc.rero.ch/record/24833/files/haa_iri.pdf|url-status=live}}</ref>

===Fitness and homozygosity===
In single-queen colonies, the level of queen [[Zygosity#Types|homozygosity]] is negatively associated with colony age.<ref name=Haag-Liautard>{{cite journal |vauthors=Haag-Liautard C, Vitikainen E, Keller L, Sundström L |title=Fitness and the level of homozygosity in a social insect |journal=Journal of Evolutionary Biology |volume=22 |issue=1 |pages=134–42 |year=2009 |pmid=19127611 |doi=10.1111/j.1420-9101.2008.01635.x |url=http://doc.rero.ch/record/11248/files/haag_flh.pdf |doi-access=free |access-date=2019-09-25 |archive-date=2021-02-27 |archive-url=https://web.archive.org/web/20210227132228/http://doc.rero.ch/record/11248/files/haag_flh.pdf |url-status=live }}</ref>  Reduced colony survival appears to be due to reduced queen lifespan resulting from queen homozygosity.

Worker homozygosity appeared to affect reproductive allocation, with higher homozygosity being associated with less resources being allocated to the sexual brood and more to worker production.<ref name=Haag-Liautard />

===Haplodiploidy===
''F. exsecta'', much like other insects in the order [[Hymenoptera]], have a [[haplodiploid]] sex determination system. An unusual 0.75 [[Coefficient of relationship|relatedness coefficient]] between full haplodiploid sisters is one of the main contributors to the frequency of evolution of eusocial species.<ref>{{cite journal|last=Foster|first=K.|author2=Wenseleers, T.|author3=Ratnieks, F.|title=Kin selection is the key to altruism|journal=Trends in Ecology & Evolution|date=1 February 2006|volume=21|issue=2|pages=57–60|doi=10.1016/j.tree.2005.11.020|pmid=16701471|bibcode=2006TEcoE..21...57F |url=https://lirias.kuleuven.be/handle/123456789/69591|url-access=subscription}}</ref>  The queen's eggs that are fertilized grow into [[diploid]] daughters, which contain two pairs of chromosomes, whereas unfertilized eggs produce [[haploid]] males, which only contain the queen's chromosomes. The voluntary fertilization of eggs is done by the egg-laying mother. Therefore, ideally, the queen's best reproductive interest is to lay a larger quantity of eggs or increase the number of eggs that produce individuals that can reproduce themselves. However,  female-rich colonies emphasized the production of workers rather than gynes.<ref>{{cite journal|last=Kummerli|first=R.|author2=Keller, L.|title=Reproductive specialization in multiple-queen colonies of the ant ''Formica exsecta''|journal=Behavioral Ecology|date=13 December 2006|volume=18|issue=2|pages=375–383|doi=10.1093/beheco/arl088|url=http://doc.rero.ch/record/302502/files/arl088.pdf|doi-access=free|access-date=18 September 2019|archive-date=16 May 2024|archive-url=https://web.archive.org/web/20240516204816/http://doc.rero.ch/record/302502/files/arl088.pdf|url-status=live}}</ref>