Individual size as determinant of sugar responsiveness in ants

Abstract: Social insects commonly exhibit division of labor in non-reproductive tasks. Task allocation may be related to size, form, and ergonomic differences when workers are anatomically variable. Carpenter ants Camponotus mus collecting nectar exhibit a wide forager size variation, thus raising t...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Josens, R., Lopez, M.A., Jofré, N., Giurfa, M.
Formato: JOUR
Materias:
ant
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_03405443_v72_n10_p_Josens
Aporte de:
id todo:paper_03405443_v72_n10_p_Josens
record_format dspace
spelling todo:paper_03405443_v72_n10_p_Josens2023-10-03T15:25:44Z Individual size as determinant of sugar responsiveness in ants Josens, R. Lopez, M.A. Jofré, N. Giurfa, M. Carpenter ants Nectar foraging Sucrose threshold Worker size ant foraging behavior individual variation laboratory method nectar resource allocation size distribution social insect speciation (biology) sugar threshold Camponotus Camponotus mus Formicidae Hexapoda Abstract: Social insects commonly exhibit division of labor in non-reproductive tasks. Task allocation may be related to size, form, and ergonomic differences when workers are anatomically variable. Carpenter ants Camponotus mus collecting nectar exhibit a wide forager size variation, thus raising the question of whether large and minor workers differ in their gustatory responsiveness and specialize, therefore, on different nectar sources. To answer this question, we first established the sucrose concentration at which small and large ants in the laboratory respond appetitively to a sugar solution (sucrose acceptance threshold, SAT) after experiencing a high or a low starvation regime (4- or 1-day carbohydrate deprivation, respectively). Under high starvation, no differences in SATs were found between larger and smaller ants. Under low starvation, both sizes increased their SATs but larger ants had a higher SAT, thus preferring more concentrated solutions while smaller ants responded mostly to more diluted sucrose solutions. In a field assay in which the distribution of larger and smaller ants on sugary food sources was analyzed, small and medium ants were found—in different proportions—at all food sources while larger ants were only found at nectar sources with a higher sugar flow rate, i.e., providing more sugar per unit time. Both field and laboratory assays supported that sugar-related parameters act as determinants of the size distribution of ants among food sources. In addition, interindividual differences in alternative non-sugar-related variables may contribute to this distribution, leading thereby to a potential nectar foraging specialization. Significance statement: Task specialization is crucial for the ecological success of social insects. Carpenter ants allocate individuals of variable size to foraging, thus raising the question of whether they differ in their food preferences. We determined the sugar concentration at which an appetitive response occurs in small and large carpenter ants, and analyzed their distribution on natural and artificial nectar sources in a field assay. Under low starvation, larger ants responded more than smaller ants to higher sucrose concentrations. Coincidently, in the field assay, they were mainly present at sources with higher sucrose delivery. This kind of specialization may reflect the fact that larger ants have larger feeding apparatuses, which may confer a better capacity to deal with the higher viscosity of more concentrated nectars and allow collecting more food at nectaries with higher sugar flow rates. Size specialization may thus increase colony success in the exploitation of variable food sources. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_03405443_v72_n10_p_Josens
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Carpenter ants
Nectar foraging
Sucrose threshold
Worker size
ant
foraging behavior
individual variation
laboratory method
nectar
resource allocation
size distribution
social insect
speciation (biology)
sugar
threshold
Camponotus
Camponotus mus
Formicidae
Hexapoda
spellingShingle Carpenter ants
Nectar foraging
Sucrose threshold
Worker size
ant
foraging behavior
individual variation
laboratory method
nectar
resource allocation
size distribution
social insect
speciation (biology)
sugar
threshold
Camponotus
Camponotus mus
Formicidae
Hexapoda
Josens, R.
Lopez, M.A.
Jofré, N.
Giurfa, M.
Individual size as determinant of sugar responsiveness in ants
topic_facet Carpenter ants
Nectar foraging
Sucrose threshold
Worker size
ant
foraging behavior
individual variation
laboratory method
nectar
resource allocation
size distribution
social insect
speciation (biology)
sugar
threshold
Camponotus
Camponotus mus
Formicidae
Hexapoda
description Abstract: Social insects commonly exhibit division of labor in non-reproductive tasks. Task allocation may be related to size, form, and ergonomic differences when workers are anatomically variable. Carpenter ants Camponotus mus collecting nectar exhibit a wide forager size variation, thus raising the question of whether large and minor workers differ in their gustatory responsiveness and specialize, therefore, on different nectar sources. To answer this question, we first established the sucrose concentration at which small and large ants in the laboratory respond appetitively to a sugar solution (sucrose acceptance threshold, SAT) after experiencing a high or a low starvation regime (4- or 1-day carbohydrate deprivation, respectively). Under high starvation, no differences in SATs were found between larger and smaller ants. Under low starvation, both sizes increased their SATs but larger ants had a higher SAT, thus preferring more concentrated solutions while smaller ants responded mostly to more diluted sucrose solutions. In a field assay in which the distribution of larger and smaller ants on sugary food sources was analyzed, small and medium ants were found—in different proportions—at all food sources while larger ants were only found at nectar sources with a higher sugar flow rate, i.e., providing more sugar per unit time. Both field and laboratory assays supported that sugar-related parameters act as determinants of the size distribution of ants among food sources. In addition, interindividual differences in alternative non-sugar-related variables may contribute to this distribution, leading thereby to a potential nectar foraging specialization. Significance statement: Task specialization is crucial for the ecological success of social insects. Carpenter ants allocate individuals of variable size to foraging, thus raising the question of whether they differ in their food preferences. We determined the sugar concentration at which an appetitive response occurs in small and large carpenter ants, and analyzed their distribution on natural and artificial nectar sources in a field assay. Under low starvation, larger ants responded more than smaller ants to higher sucrose concentrations. Coincidently, in the field assay, they were mainly present at sources with higher sucrose delivery. This kind of specialization may reflect the fact that larger ants have larger feeding apparatuses, which may confer a better capacity to deal with the higher viscosity of more concentrated nectars and allow collecting more food at nectaries with higher sugar flow rates. Size specialization may thus increase colony success in the exploitation of variable food sources. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
format JOUR
author Josens, R.
Lopez, M.A.
Jofré, N.
Giurfa, M.
author_facet Josens, R.
Lopez, M.A.
Jofré, N.
Giurfa, M.
author_sort Josens, R.
title Individual size as determinant of sugar responsiveness in ants
title_short Individual size as determinant of sugar responsiveness in ants
title_full Individual size as determinant of sugar responsiveness in ants
title_fullStr Individual size as determinant of sugar responsiveness in ants
title_full_unstemmed Individual size as determinant of sugar responsiveness in ants
title_sort individual size as determinant of sugar responsiveness in ants
url http://hdl.handle.net/20.500.12110/paper_03405443_v72_n10_p_Josens
work_keys_str_mv AT josensr individualsizeasdeterminantofsugarresponsivenessinants
AT lopezma individualsizeasdeterminantofsugarresponsivenessinants
AT jofren individualsizeasdeterminantofsugarresponsivenessinants
AT giurfam individualsizeasdeterminantofsugarresponsivenessinants
_version_ 1807315592529575936