Search results for "Predator"
showing 10 items of 349 documents
Late Jurassic globetrotters compared: A closer look at large and giant theropod tracks of North Africa and Europe
2019
Abstract Late Jurassic theropod tracks are very common both in North Africa and Europe. Two recently described ichnotaxa Megalosauripus transjuranicus and Jurabrontes curtedulensis from the Kimmeridgian of Switzerland show the coexistence of two apex predators in the same palaeoenvironment. Similar tracks can be found in tracksites from the Iberian Peninsula and from Morocco. Here, we further explore the similarities among the Swiss ichnotaxa and the other tracks from Germany (Kimmeridgian), Spain (Tithonian-Berriasian), Portugal (Oxfordian-Tithonian) and Morocco (Kimmeridgian) through novel three-dimensional data comparisons. Specimens were grouped in two morphotypes: 1) large and gracile …
La ética en el otorgamiento y gestión del crédito: “Prácticas predatorias y abusivas en la financiación hipotecaria a inmigrantes ecuatorianos en Esp…
2019
1.- Antecedentes y Justificativo Esta investigación se planteó a partir de los datos alarmantes de ecuatorianos inmigrantes en España involucrados en el endeudamiento hipotecario y la situación apremiante ante los numerosos casos de crédito fallido (default), desahucios y el crecimiento de demandas judiciales que afectaban a este colectivo. El autor, partícipe como asesor en el Programa de Asistencia de Asesoría Jurídica Hipotecaria para ecuatorianos afectados por las Hipotecas, desarrollado entre los años 1999 y 2007 por los Consulados y la Embajada de Ecuador en España, se vio motivado a investigar sobre las causas del default de los créditos hipotecarios del colectivo y a reflexionar sob…
Research data supporting "Social information use about novel aposematic prey is not influenced by a predator’s previous experience with toxins"
2019
This data is from the experiment investigating social avoidance learning in wild-caught great tits, conducted at Konnevesi Research Station in Central Finland during winter 2017. Sheet 1 (���main data���) contains data from the main avoidance learning experiment, including individual attributes (sex, age, weight etc.), experimental treatments and individuals��� foraging choices in the learning trials. Sheet 2 (���preference test���) contains data from the initial preference test of the symbols that were used in the experiment, and Sheet 3 (���visibility test���) data from the initial visibility test of the same symbols.
The carabid Pterostichus melanarius uses chemical cues for opportunistic predation and saprophagy but not for finding healthy prey
2017
The sentinel prey method can quantify predation pressure in various habitats. Real prey is assumed to more realistically mimic the predator experience but the predator can rarely be identified. Artificial prey made of plasticine may lack real chemical cues, but provides information about predator identity. However, the relationship between predation pressure registered by artificial versus real prey is not clear. We tested the relative attractiveness of artificial caterpillars, and intact, wounded, or dead larvae of the cabbage moth (Mamestra brassicae) for the carabid predator Pterostichus melanarius Illiger (Coleoptera: Carabidae). P. melanarius adults were attracted to dead caterpillars …
Breeding near heterospecifics as a defence against brood parasites: can redstarts lower probability of cuckoo parasitism using neighbours?
2022
Breeding habitat choice based on the attraction to other species can provide valuable social information and protection benefits. In birds, species with overlapping resources can be a cue of good quality habitats; species with shared predators and/or brood parasites can increase joint vigilance or cooperative mobbing, while raptors may provide a protective umbrella against these threats. We tested whether the migratory common redstart (Phoenicurus phoenicurus) is attracted to breed near active nests of the great tit (Parus major), a keystone-information source for migrant passerine birds, or a top predator, the northern goshawk (Accipiter gentilis). This system is unique to test these quest…
Littoral-pelagic zone food web interactions in fishless, highly humic Lake Mekkojärvi
2007
Return of the Apex Predator : How Brown Trout (Salmo trutta) Re-Establishment Shapes an Ecosystem
2021
Re-establishment of a declined apex predator fish species in a lake ecosystem may have dramatic effects on other fish and plankton community already inhabiting the ecosystem. We studied mechanistically potential impacts of re-establishment of the brown trout (Salmo trutta) in the west-central European Lake Constance focusing on two commercially important fish species: whitefish and Eurasian perch. We compared simulation model outputs from two versions of an allometric trophic network model for Lake Constance, one with and one without the trout as the apex predator. The re-establishment of the declined brown trout reduced the perch population directly by predation and indirectly by increased…
Predation on sea urchin by Marthasterias glacialis (L.).
2013
Nesting behaviour and description of mature larva of Lindenius albilabris (Fabricius, 1793) (Hymenoptera: Crabronidae)
2022
Nesting habits of the digger wasp Lindenius albilabris (Fabricius, 1793) at two localities in Poland were studied. The female hunts nymphs or adults of plant bugs Lygus rugulipennis Poppius, 1911 and L. pratensis (Linnaeus, 1758), depositing up to 10 individuals per cell, depending on their size. Nests are built in a wide variety of sandy habitats, on dirt roads, and in wastelands. The nest consists of a 10–12 cm long main burrow and one to three cells. Males are usually found on flowers of wild carrots Achillea millefolium, Daucus carota, Peucedanum oreoselinum, Pimpinella sp. and Tanacetum vulgare. The nest kleptoparasite Metopia argyrocephala was recorded in nests of this species. The ma…
Antipredatory function of head shape for vipers and their mimics.
2011
Most research into the adaptive significance of warning signals has focused on the colouration and patterns of prey animals. However, behaviour, odour and body shape can also have signal functions and thereby reduce predators' willingness to attack defended prey. European vipers all have a distinctive triangular head shape; and they are all venomous. Several non-venomous snakes, including the subfamily Natricinae, commonly flatten their heads (also known as head triangulation) when disturbed. The adaptive significance of this potential behavioural mimicry has never been investigated. We experimentally tested if the triangular head shape typical of vipers offers protection against predation.…