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N.R. Franks and C. Tofts' simulations of foraging for work algorithm to explain reality of aged-based division of labour in social insects suffer from numerous drawbacks, and offer inadequate and unreal simulation results. Franks and Tofts fail to refute the existence of a causal link between age and behavior due to lack of a formal mathematical proof. The mathematical model looses its claimed flexible, robust and efficient explanation of division of labor due to an inadequate algorithm system, circular arguments and a lack of focus on biological aspects of insects.

Background. Several anatomical studies provide evidence that green turtles (Chelonia mydas) possess the necessary anatomy for colour vision. Behavioural experiments have previously been conducted with newly emerged hatchlings, concluding that they are attracted to shorter wavelengths compared to longer wavelengths within a terrestrial environment, suggesting a possible attraction towards blue. This paper assessed the colour vision of hatchlings within an aquatic environment, and investigated whether the attraction for shorter wavelengths remains consistent within water, whether the colour saturation of the chromatic stimuli was an important factor, and whether rearing and testing individual animals in different coloured housing tanks has an impact on their visual choices. Methods. Forty-one hatchling green turtles were presented with a three-choice experiment where food was attached to three different coloured plates. The plates (blue, yellow, and red) were randomly arranged in the turtle's tank and four different colour saturations were tested (100, 75, 50, and 25%). Turtles were individually placed into their housing tanks (coloured either red, white, blue or grey) with three different colour plates in front of them, from the same saturation level. The colour of the plate with food first approached and bitten by the turtle was recorded. Results. The colour of the tank in which an individual was reared, and where experiments were conducted, significantly influenced which food item was selected on the different coloured plates. While individual turtles preferred to select the food items associated with blue plates across the entire experiment (66.1% of the time compared to 18.2% and 15.7% for yellow and red plates respectively), the preference for blue plates was influenced by the colour of the rearing/experimental tank. Individuals raised in red, white or blue tanks appeared to consistently prefer food on blue plates, but there appeared to be no plate colour preference by turtles in grey tanks. There was no significant effect of either colour saturation or the spatial arrangement of the three colours within an experimental tank on colour choice, and no significant interaction between tank colour and colour saturation. Discussion. These findings confirm that the terrestrial preference towards shorter wavelength colours, such as blue, compared to longer wavelength colours remains consistent within an aquatic environment. This preference for blue continues even as the colour saturation reduces from 100% down to 25%, and the colours become darker. Thus, it is suggested that green turtle hatchlings have a strong attraction towards blue. This attraction, however, is influenced by the colour of the tank the turtles were raised in. While this supports the notion that environmental colour may influence individual turtle visual capabilities, it suggests that this relationship is more complicated, and requires further investigation. [ABSTRACT FROM AUTHOR]

The evolution of nest weaving, the inclusion of larval silk in the nest walls, is considered one of the pinnacles of cooperative behaviour in social insects. Within the four ant genera in which this has evolved, Oecophylla are unique in being the only group that precedes the deposition of larval silk by actively manipulating the leaf substrate to form a nest chamber. Here we provide the first descriptions of the manipulation process within a complex-systems framework. Substrate manipulation involves individual ants selecting, grasping and attempting to pull the edge of the substrate. These individuals are then joined by nest mates at the work site, who either select a site beside the first individual or grasp the body of the first or preceding worker to form a chain of pulling ants that together drag and bend the substrate. Site selection by individual workers is not random when confronted with an artificial leaf, with individuals more likely to grasp a substrate at its tip rather than along a more broad edge. The activity of additional individuals is also not random, with their activity being grouped in both space and time. Additional individuals are more likely to join an existing biting individual or pulling group. The positive feedback associated with the early stages of pulling behaviour appears typical for many of the collective actions observed in social insects. [ABSTRACT FROM AUTHOR]

The evolution of nest weaving, the inclusion of larval silk in the nest walls, is considered one of the pinnacles of cooperative behaviour in social insects. Within the four ant genera in which this has evolved, Oecophylla are unique in being the only group that precedes the deposition of larval silk by actively manipulating the leaf substrate to form a nest chamber. Here we provide the first descriptions of the manipulation process within a complex-systems framework. Substrate manipulation involves individual ants selecting, grasping and attempting to pull the edge of the substrate. These individuals are then joined by nest mates at the work site, who either select a site beside the first individual or grasp the body of the first or preceding worker to form a chain of pulling ants that together drag and bend the substrate. Site selection by individual workers is not random when confronted with an artificial leaf, with individuals more likely to grasp a substrate at its tip rather than along a more broad edge. The activity of additional individuals is also not random, with their activity being grouped in both space and time. Additional individuals are more likely to join an existing biting individual or pulling group. The positive feedback associated with the early stages of pulling behaviour appears typical for many of the collective actions observed in social insects. [ABSTRACT FROM AUTHOR]

The Australian intertidal ant, Polyrhachis sokolova lives in mudflat habitats and nests at the base of mangroves. They are solitary foraging ants that rely on visual cues. The ants are active during low tides at both day and night and thus experience a wide range of light intensities. We here ask the extent to which the compound eyes of P. sokolova reflect the fact that they operate during both day and night. The ants have typical apposition compound eyes with 596 ommatidia per eye and an interommatidial angle of 6.0°. We find the ants have developed large lenses (33 µm in diameter) and wide rhabdoms (5 µm in diameter) to make their eyes highly sensitive to low light conditions. To be active at bright light conditions, the ants have developed an extreme pupillary mechanism during which the primary pigment cells constrict the crystalline cone to form a narrow tract of 0.5 µm wide and 16 µm long. This pupillary mechanism protects the photoreceptors from bright light, making the eyes less sensitive during the day. The dorsal rim area of their compound eye has specialised photoreceptors that could aid in detecting the orientation of the pattern of polarised skylight, which would assist the animals to determine compass directions required while navigating between nest and food sources. [ABSTRACT FROM AUTHOR]

The pressure of returning to and locating the nest after a successful foraging trip is immense in ants. To find their way back home, ants use a number of different strategies (e.g. path integration, trail following) and rely on a range of cues (e.g. pattern of polarised skylight, landmark panorama) available in their environment. How ants weigh different cues has been a question of great interest and has primarily been addressed in the desert ants from Africa and Australia. We here identify the navigational abilities of an intertidal ant, Polyrhachis sokolova, that lives on mudflats where nests and foraging areas are frequently inundated with tidal water. We find that these solitary foraging ants rely heavily on visual landmark information for navigation, but they are also capable of path integration. By displacing ants with and without vector information at different locations within the local familiar territory, we created conflicts between information from the landmarks and information from the path integrator. The homing success of full-vector ants, compared with the zero-vector ants, when displaced 5?m behind the feeder, indicate that vector information had to be coupled with landmark information for successful homing. To explain the differences in the homing abilities of ants from different locations we determined the navigational information content at each release station and compared it with that available at the feeder location. We report here the interaction of multiple navigation strategies in the context of the information content in the environment. [ABSTRACT FROM AUTHOR]

The article examines the distribution of the flying-fox species Pteropus conspicillatus and Pteropus poliocephalus at Finch Hatton in mid-eastern Queensland. Large flying foxes are known for their capability of making long-distance flights over a sustained period of time. To determine if the location is climatically suitable for the species, climatic models were developed from previous records. Findings showed that P. poliosephalus had a higher climatic suitability at the site. There have been historical records for poliocephalus and the location of the flying-fox camp is the most southerly distribution for conspicillatus.

Recognition systems involve 3 components: an expression component, a perception component, and an action or response component. Disentangling the perception component from the action component can be difficult, as the absence of a discriminatory response may result from either a difference in perception or action. Social insects generally defend their colony against intruding conspecifics and provide a useful model for exploring recognition systems. However, whether differences in behavior at the colony or individual level result from the perception or action component of the recognition system is largely unknown. Furthermore, variation at the individual level has remained largely unexplored because research on social insects often focuses on the colony rather than on the individual. Using some novel behavioral bioassays, we here show that variation in the aggressive behavior of individual weaver ants (Oecophylla smaragdina L.) arises more from the identity of the recipient than of the intruder and, contrary to previous findings, that this often results from perceptual differences. We suggest that recognition in weaver ants may involve a template based on the individual’s odor prior to intermingling with other odors rather than on a common odor. We also argue that a common odor might be more important for the survival of the colony than a shared template. Conversely, possessing a range of templates may provide a colony with additional fitness benefits. By focusing on the differences among individual workers within colonies, this study reveals complexities in nest mate recognition that might otherwise have gone unnoticed. [ABSTRACT FROM PUBLISHER]

The article presents a study on ground dwelling ants in areas of Australian Wet Tropics which have high biodiversity value above a small spatial scale. The three measures of biodiversity used in the study include estimated species richness, complementarity analysis, and evolutionary history. Results show that species richness is consistent at lower elevations but decreases at higher elevations. Moreover, narrow altitudinal range of the ants was seen in the complementarity analysis.