Cataglyphis (original) (raw)
Related papers
2009
Cataglyphis ants comprise one of the most characteristic groups of insects in arid regions around the Mediterranean basin and have been intensively studied over the last 30 years. These ants are central-place foragers and scavengers, single-prey loaders that have become a model for insect navigation using sophisticated visual orientation, having lost pheromone orientation. They are highly heat-tolerant ants that forage close to their critical thermal limit during the hottest hours of the day, with their long-chain cuticular hydrocarbons protecting them from desiccation. This is exemplified in two Cataglyphis species, each of which developed different mechanisms for counteracting extreme heat when foraging: polymorphism of workers vs. physiological and behavioral adaptations. Several species in this genus have also become a model for studying nestmate recognition mechanisms. The role of cuticular hydrocarbons and the postpharyngeal gland as a reservoir of hydrocarbons in nestmate recognition was initially discovered mainly in Cataglyphis, including the first experimental demonstration of the Gestalt model of nestmate recognition. These ants possess very acute discrimination capacities, down to individual recognition. Such fine discrimination is seemingly used by ants that rescue from ant-lion traps only those individuals that are their nestmates. Two main reproductive strategies are exhibited by species of this genus: some reproduce classically, by independent colony foundation following nuptial flight, whereas others reproduce by colony fission. Limited dispersion increases competition for access to resources, and local resource competition
Environmental Entomology, 1990
Critical thermal (CT) maxima (CTMAX) and critical thermal minima (CTMIN) were determined for minor caste workers of the red imported fire ant, Solenopsis inoicta Buren. Ants were tested from polygynous colonies collected from northwestern Texas. Mean CTMAX is lower than that reported for the upper lethal temperature for short exposures and higher than that reported for the upper foraging limit. Mean CTMIN was, likewise, lower than the reported lower foraging limit. The CT values obtained at weekly intervals as colony maintenance temperatures were reduced from 29 to g°C showed significant reductions in both CTMAX and CTMIN. The CT values averaged 40.7 (MAX) and 3.6"C (MIN). Differences between critical thermal values and those reported in previous studies of lethal and foraging temperatures are discussed.
Allometry of Workers of the Fire Ant, Solenopsis invicta
Journal of Insect Science, 2003
The relationship between worker body size and the shape of their body parts was explored in the polymorphic ant, Solenopsis invicta. The data consisted of 20 measurements of body parts as well as sums of some of these measurements. Size-free shape variables were created by taking the ratios of relevant measures. After log-transformation, these ratios were regressed against the logarithm of total body length, or against the log of the size of the parent part. Slopes of zero indicated that shape did not change with size, and non-zero slopes signaled a size-related change of shape. Across the range of worker sizes, the head length retained a constant proportion to body length, but relative headwidth increased such that head shape changed from a barrel-profile to a somewhat heart-shaped profile. Antennae became relatively smaller, with the club contributing more to this decline than the other parts. The alinotum became relatively shorter and higher (more humped), and the gaster increased in both relative width and length, and therefore in volume. All three pairs of legs were isometric to body length. The component parts of the legs, with one exception, were isometric to their own total leg length. The body of S. invicta is therefore dominated by mostly modest allometries, giving large workers a somewhat different shape than small ones. None of these size-shape relationships was different for different colonies. The functional meaning of these shape changes is unknown, but that does not stop us from speculating.
The ontogeny of foragwehaviour in desert ants, Cataglyphis bicolor
Ecological Entomology, 2004
1. Individually foraging desert ants, Cataglyphis bicolor, exhibit short foraging lives (half lifetime, i.e. half-time of the exponential decay function: 4.5 days), in which they perform 3.7 AE 1.9 foraging runs per day. 2. During their short lifetime foraging period the ants increase the duration of their foraging round trips (up to 40.0 AE 24.6 min per run), the maximal distance of individual foraging runs (up to 28.2 AE 4.1 m), and their foraging success, i.e. the ratio of successful runs to the total number of runs (up to 0.70). 3. The parameter that increases most dramatically during a forager's lifetime is direction fidelity, i.e. the tendency to remain faithful to a particular foraging direction. 4. A model based on some simple behavioural rules is used to describe the experimental findings that within an isotropic food environment individual ants develop spatial foraging idiosyncrasies, and do so at a rate that increases with the food densities they encounter. 5. Finally, it is argued that in functional terms direction fidelity is related to the navigational benefits resulting from exploiting familiar (route-based) landmark information, and hence reduces round-trip time and by this physiological stress and predatory risk.
Social Life in Arid Environments: The Case Study of Cataglyphis Ants
Annual review of entomology, 2016
Unlike most desert-dwelling animals, Cataglyphis ants do not attempt to escape the heat; rather, they apply their impressive heat tolerance to avoid competitors and predators. This thermally defined niche has promoted a range of adaptations both at the individual and colony levels. We have also recently discovered that within the genus Cataglyphis there are incredibly diverse social systems, modes of reproduction, and dispersal, prompting the tantalizing question of whether social diversity may also be a consequence of the harsh environment within which we find these charismatic ants. Here we review recent advances regarding the physiological, behavioral, life-history, colony, and ecological characteristics of Cataglyphis and consider perspectives on future research that will build our understanding of organic adaptive responses to desertification. Expected final online publication date for the Annual Review of Entomology Volume 62 is January 07, 2017. Please see http://www.annualre...