Search results for "Animal Science and Zoology"
showing 10 items of 2095 documents
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…
Trichromatic color vision in the salamander (Salamandra salamandra)
1995
Spectral sensitivity functions were measured between 334 nm and 683 nm in Salamandra salamandra by utilizing two behavioral reactions: the negative phototactic response, and the prey catching behavior elicited by a moving worm dummy. The action spectrum of the negative phototactic response revealed 3 pronounced maxima: at 360–400 nm, at 520–540 nm, and at 600–640 nm. In the range around 450 nm, there was a “reaction gap” where sensitivity could not be measured. The action spectrum of the prey catching behavior was entirely different: maximal sensitivity was found at 500 nm and at 570 nm. Between 500 nm and 334 nm sensitivity decreased continuously for about 1 log unit (Fig. 6).
Individual color variation and male quality in pied flycatchers (Ficedula hypoleuca): a role of ultraviolet reflectance
2002
Bright coloration of males in many animal species has inspired researchers for more than a century. In this field study, we investigated whether color variation between individuals is related to individual quality in pied flycatcher (Ficedula hypoleuca) males in terms of arrival time at the breeding sites. In addition to traditional visual color scoring, plumage color was measured using spectroradiometric measurements between 320 and 700 nm. This range includes the near-ultraviolet waveband from 320 to 400 nm. Males that arrived earlier at breeding sites had higher proportional UV reflectance in the crown and mantle. The proportional UV reflectance in the crown and mantle was not related to…
Die Ölblumensymbiosen - Parallelismus and andere Aspekte ihrer Entwicklung in Raum and Zeit1, 2
2009
The oil-bee/oil-flower relationships: parallelism and other aspects of their evolution in space and time A survey is given of our present knowledge and existing hypotheses concerning the biogeography, history, and phylogeny of plant taxa yielding fatty oil as a floral reward, and of the bee genera involved in their pollination. Four syngenetic complexes of the symbiosis arose convergently: The neotropical, the paleotropical, the holarctic, and the capensic complex. On the basis of the mutual structural adaptations of bees and flowers it is concluded that, in addition, parallelism within related groups as a result of a common tendency to develop the respective organs, has played an important…
Territorial song and song neighbourhoods in the Scarlet Rosefinch Carpodacus erythrinus
2000
Throughout the range of the Scarlet Rosefinch, its territorial song consists of 3–9 (usually 4–5) elements, of which there are 5 different types. The differences lie in the way the pitch of the element changes in time (frequency “slope”) and the width of the frequency band. Within a given type of song, the various elements can be present in almost any combination. Therefore, so many song types can be formed that the songs in even small parts of the species’ area are clearly distinct from one another. Despite this capacity for variation, however, by chance identical songs may be sung in widely separated parts of the area, in some cases by different subspecies. The species has not developed l…
Sister species within the Triops cancriformis lineage (Crustacea, Notostraca)
2006
301 Korn, M., Marrone, F., Perez-Bote, J. L., Machado, M., Cristo, M., Cancela da Fonseca, L. & Hundsdoerfer, A. K. (2006). Sister species within the Triops cancriformis lineage (Crustacea, Notostraca). — Zoologica Scripta , 35 , 301–322. We investigated the phylogenetic relationships among the three presently recognized subspecies of the tadpole shrimp, Triops cancriformis , using mitochondrial 16S and 12S rDNA sequences. Our results indicate that the taxon is divided into two distinct lineages. One lineage is formed of T. c. cancriformis populations and samples from northern Spain that had been classified as T. c. simplex in the most recent literature. The second lineage comprises all pop…
Regional and age-dependent differences in the effect of wind on the migratory routes of Eleonora's Falcon.
2015
During migration, birds can show different responses to wind in relation to distance to the goal, experience, ecological barriers and visibility of landmarks. We analysed the effect of wind (tailwinds and crosswinds) on daily movement rates (forward and perpendicular) of Eleonora’s falcons using ARGOS satellite telemetry, during their trans-continental autumn migration to Madagascar, in relation to the different crossed regions and individuals’ age class. Our results showed that the effect of wind on daily movement rates was not uniform, being stronger in the farthest region from the migration goal, the Sahara desert, with adults being more affected than juveniles in this region. In the Sah…
Near infrared reflectance spectroscopy (NIRS) characterization of European sea bass (Dicentrarchus labrax) from different rearing systems
2009
The present study aimed to predict by NIRS the proximate chemical composition and some carcass traits of sea bass coming from 11 farms with different rearing systems (extensive, intensive in land-based basins, sea cages) and located in northern (Friuli, Veneto), central (Tuscany) and southern (Puglia and Sicily) Italy. NIRS analysis of freeze dried sea bass fillets gave fairly good predictions of slaughter weight and fillet yield (R2cv=0.48-0.55), while results for carcass yield were poor. NIRS analysis was highly predictive for the condition factor (R2cv=0.790, SECV=0.09) and for water, ether extract and gross energy showing high correlations (R2cv>0.90) with NIR spectral infor- mation and…
Female Attraction Behaviour of Radio Tagged Polyterritorial Pied Flycatcher Males
1993
AbstractPolygynous mating is costly for pied flycatcher (Ficedula hypoleuca) females. Thus, females have a good reason to attempt to avoid mating with already mated polyterritorial males. One cue to disclose a male's mating status is his behaviour. The behaviour of polyterritorial and unmated males was studied by radio tagging that allows accurate recording of male movements. While attracting a secondary female polyterritorial males spent significantly less time on the secondary territory than did unmated males on their single territory. Polyterritorial males also tended to have lower song rates. When a female appeared on the secondary territory of polyterritorial males, they increased the …
<strong>Pamphagidae (Orthoptera: Caelifera) of North Africa: key to genera and the annotated check-list of species</strong>
2013
At least 95 species of Pamphagidae belonging to 17 genera are known in North Africa. Taxonomic status is fairly known, with some exception, mainly due to scarcity of available specimens of some genera in museums and collections. In this paper, the author proposes a new key to genera and reports the annotated list of all the known species, based on specimens examined in different European museums. Concerning the subfamily Thrinchinae, he proposes to consider only the following species of the genus Tmethis: T. cisti, T. harterti new status, T. maroccanus and T. pulchripennis. He also considers Neotmethis bidentatus synonym of T. harterti, and the three newly described species of the genus Tua…