Search results for "Fora"
showing 10 items of 1086 documents
Age and ovarian development are related to worker personality and task allocation in the ant Leptothorax acervorum
2014
Abstract In social insects, workers of different morphological castes and age are known to act differently. Yet, it is unclear how body size and ovarian development influence worker personalities (i.e. consistent behavioral variation) and task allocation in similar aged ant workers of monomorphic species. Behavioral variation is thought to be a key element of division of labor, but few studies have linked worker personality to task allocation. We investigated individual behavior in Leptothorax acervorum ant workers at two time points during the first three months of their life and in two different settings. We observed worker behavior in the nest (i.e. task allocation) and in standardized a…
Predatory behavior in the genusLeptogenys: A comparative study
1997
We studied the predatory behavior of seven species of the genusLeptogenys from Mexico and Cameroon. The ants of this genus are armed with long, thin, curved mandibles articulated at the extreme corners of the anterior margin of the head, permitting them easily to seize oniscoid isopods, the obligate or the principal prey of mostLeptogenys species. Workers hunt these prey, which are able to roll themselves up, solitarily. Foraging behavior comprises sequences of up to eight activities. The prey can be seized by the body (rolled up or not), or alternatively by the edge of the shell, then turned over and stung on the ventral face. A relationship between the mandible size of the workers and the…
Behavioural responses of Eurasian treecreepers, Certhia familiaris, to competition with ants
1997
Competition for a specific resource that is essential for the survival of both the competitors may be intense even between very dissimilar taxa. However, the importance of the effects caused by such interspecific competition has seldom been emphasized. These effects can appear as differences in individual foraging behaviour during the breeding season, which can result in critical variation in fitness. In this study we examined the effects of wood ants (Formica rufa group) on the abundance of other invertebrates on tree trunks and on the foraging site selection of breeding Eurasian treecreepers, which use the same habitat as wood ants. Arthropods were scarcer on the trunks with ants present;…
Personality and body condition have additive effects on motivation to feed in Zebra Finches Taeniopygia guttata
2012
Several hypotheses have been proposed to account for the adaptive evolution of person-ality, defined as inter-individual differences in behaviour that are consistent over timeand across situations. For instance, the ‘pace-of-life syndrome’ hypothesis suggests thatpersonality evolved as a behavioural correlate of life-history trajectories that vary withinpopulations. Thus, proactivity, corresponding to higher exploratory tendencies or higherboldness levels, has been linked to higher productivity or mortality rates. However, theextent to which proactivity is associated with a higher motivation to forage remainspoorly understood. Moreover, although personality and its effects on foraging behavi…
Feeding ecology of the loggerhead turtle Caretta caretta in the western Mediterranean
2001
We studied the feeding ecology of juvenile loggerhead turtles Caretta caretta in the western Mediterranean based on the contents of the digestive tract of 54 turtles (range of CCL: 34–69 cm) seized in Barcelona (Spain) in 1991. Turtles had been captured in fishing trawls, but specific information about dates and localities is not available. Despite this limitation, we obtained interesting evidences about the foraging strategies of loggerheads, with potentially important conservation implications. We report 33 new taxa in the diet. Results indicated that western Mediterranean loggerheads feed in an opportunistic way. Numerically, fish made up the most important prey group, followed by pelagi…
Sella, A NEW NAME FOR THE GENUS Linaresia EL KADIRI, 1992 (NASSELLARIA, RADIOLARIA) PREOCCUPIED BY COPEPOD CRUSTACEANS (LAMIPPIDAE, MAXILLOPODA)
2021
The aim of this short note is to create a new name of this genus since the original name Linaresia proved to pre-exist in the paleontological literature ( Linaresia de Zulueta, 1908, Family Lamippidae, Copepod crustaceans, and Linaresia Gonzalez-Donoso, 1968, Family Gavelinellidae, Agglutinated Foraminifera). The new name created for the above mentioned radiolarians is: Sella . This name derives from an arbitrary combination of letters (International Code of Zoological Nomenclature). The type species of Sella is S. beniderkoulensis by original designation (El Kadiri, 1992).
Food-attraction conditioning in the snail, Helix pomatia
1995
Adult pulmonate snails (Helix pomatia) were released equidistant between two types of food, carrot and potato, respectively. Naive snails moved in different directions and did not locate either food above chance, although both foods were readily eaten upon direct contact. After a single carrot feeding episode, 75% of the carrot-fed snails moved directly towards the carrot and ate it. Conversely, potato-fed snails located the potato in 67% of the cases. Snails that were fed apple or lettuce behaved like naive animals, with the majority of animals (75% in both cases) locating neither the carrot nor the potato. The ability of snails to locate this particular food after a single feeding episode…
Late Quaternary high uplift rates in northeastern Sicily: evidence from calcareous nannofossils and benthic and planktonic foraminifera
2011
The northeastern part of Sicily is characterized by intense seismic activity. Several systems of faults have been recognized in Pliocene and Pleistocene sediments in the area and, in fact, estimates of uplift rates are among the highest recorded in Sicily and south Italy. We examined calcareous nannofossil and benthic and planktonic foraminifera assemblages from pelitic sediments of the Contrada Zura section (Barcellona Pozzo di Gotto Basin, Furnari village, Messina). The occurrence of Emiliania huxleyi, a coccolithophore species which appeared in the oceanic record about 270,000 years ago, is witness to the uniqueness of this outcrop, while the planktonic/benthic foraminifera ratio indicat…
Giant reed as energy crop for Southern Italy: An economic feasibility study
2016
Abstract Among renewable sources giant reed has attracted a growing interest as energy crop especially in Southern Europe, thanks to its low agronomic input requirements. This paper aimed at evaluating the economic feasibility of introduction of giant reed plantation as energy crop in the Southern Italy. In particular, an economic and financial analysis was performed by comparing giant reed (both for woodchip and chopped forage production) with traditional crops (pluriannual and annual) that are currently cultivated in the same area, such as wine grape, melon and tomato. Results showed the highest profitability of giant reed respect to other crops with current market prices. In particular, …
Behavioral response of the egg parasitoid Ooencyrtus telenomicida to host-related chemical cues in a tritrophic perspective
2010
The response of the generalist egg parasitoid Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) to host-related chemical cues from tomato plants, Solanum lycopersicum L., and adults of Nezara viridula (L.) (Heteroptera: Pentatomidae) was investigated in laboratory-based no-choice and paired-choice tests. In Y-tube olfactometer experiments, when female wasps were exposed to volatiles from plants in different conditions, they were attracted only to volatiles produced by N. viridula adult-infested tomato plants. When female wasps were exposed to adults of N. viridula, they were attracted to volatiles from virgin males, and, at a lower level, to volatiles from mated females in preov…