title: Quantity discrimination in parental fish: female convict cichlid discriminate fry shoals of different sizes.
abstract: Numerical abilities have been found to be adaptive in different contexts, including mating, foraging, fighting assessment and antipredator strategies. In species with parental care, another potential advantage is the possibility to adjust parental behavior in relation to the numerosity of the progeny. The finding that many fish vary their parental investment in relation to brood size advocates the existence of a mechanism for appraising offspring number, an aspect that has never been directly investigated. Here we tested the ability of parental female convict cichlid (Amatitlania nigrofasciata) to discriminate between two fry groups differing in number by measuring time spent attempting to recover groups of fry experimentally displaced from the next. Females spent more time trying to recover the fry from larger groups when tested with contrasts 6 versus 12 (1:2) and 6 versus 9 fry (2:3); however, they showed no preference in the 6 versus 8 (3:4) contrast, suggesting that this task exceeds their discrimination capacity.
authors.affiliation: Department of Fisheries, Faculty of Natural Resources, University of Tehran, Chamran St, PO Box: 31585-4314, Karaj, Iran.
authors.forename: Mohammad Navid
authors.initials: MN
authors.lastname: Forsatkar
authors.affiliation: Department of Fisheries, Faculty of Natural Resources, University of Tehran, Chamran St, PO Box: 31585-4314, Karaj, Iran. malahi@ut.ac.ir.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Nematollahi
authors.affiliation: Department of General Psychology, University of Padova, Padua, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Bisazza
mesh_terms: D000818:Animals; D023681:Cichlids; D003071:Cognition; D005260:Female; D008425:Maternal Behavior
keywords: Cichlid fish; Numerical ability; Numerical ratios; Parental care; Quantity discrimination