Search results for "zoo"
showing 10 items of 5964 documents
Bean goose migration shows a long-term temporal shift to earlier spring, but not to later autumn migration in Finland
2023
Ilmastonmuutos vaatii eliöitä mukauttamaan perinnöllisiä tai opittuja käyttäytymismallejaan muuttuviin ympäristöolosuhteisiin. Erityisen alttiita muutoksille voi olla erilaisten habitaattien välillä muuttavat linnut, joiden selviytyminen on yhteydessä muuton onnistuneeseen ajoittamiseen. Tässä tutkimuksessa käytimme metsähanhesta (Anser fabalis) avoimeen lintutietopalveluun, Tiiraan (tiira.fi – BirdLife Suomi), kerättyjä havaintoja selvittääksemme, onko lajin muuton ajoituksessa tapahtunut muutosta viimeisten 40 vuoden aikana. Lisäksi selvitimme ajoituksen yhteyttä muuton aikaiseen suursäätilaan käyttämällä Pohjois-Atlantin suursäätilaa kuvaavaa NAO-indeksiä. Tutkitulla ajanjaksolla 1978–20…
Vocal communication in the Iberian wolf
2015
PARTE I. COMUNICACIÓN ACÚSTICA EN EL LOBO IBÉRICO El lobo (Canis lupus) es un carnívoro social cuya unidad básica de organización social es la manada, formada básicamente por una pareja reproductora y sus descendientes de varios años (Mech 1970, 1999). El número medio de lobos que integra una manada (tamaño de grupo) oscila entre 3 y 11 individuos (Fuller et al., 2003) y, en condiciones naturales, depende en gran medida de la disponibilidad de alimento (Mech & Boitani, 2003). Uno de los comportamientos más característicos y llamativos de los lobos es la emisión de aullidos para comunicarse a largas distancias. Quizá por este motivo la comunicación acústica de los lobos ha sido objeto de est…
Sexual selection on song and cuticular hydrocarbons in two distinct populations of Drosophila montana
2011
Sexual selection has the potential to contribute to population divergence and speciation. Most studies of sexual selection in Drosophila have concentrated on a single signaling modality, usually either courtship song or cuticular hydrocarbons (CHCs), which can act as contact pheromones. We have examined the relationship between both signal types and reproductive success using F1–3 offspring of wild- collected flies, raised in the lab. We used two populations of the Holarctic species Drosophila montana that represent different phylogeographic clades that have been separate for ca. 0.5 million years (MY), and differ to some extent in both traits. Here, we characterize the nature and identify …
Zoosemiotica 2.0. Forme e politiche dell'animalità
2017
Questo volume ha tre direzioni di discorso. Innanzitutto, un dialogo fra la semiotica e le altre discipline interessate agli studi animali: la filosofia, la filosofia del linguaggio e della mente, le scienze umane e sociali, le scienze cognitive e le neuroscienze. Non a caso molti degli interventi contenuti in questo volume non sono di semiologi ma di filosofi, sociologi, antropologi, linguisti, filologi, letterati etc. In secondo luogo, una discussione interna alla semiotica, nel passaggio dalla zoosemiotica 1.0 (tradizionalmente più interessata ai linguaggi e alle forme di comunicazione delle diverse specie animali) alla zoosemiotica 2.0, di conserva con altri settori a prima vista oppost…
Sex Allocation Theory for Facultatively Sexual Organisms Inhabiting Seasonal Environments: The Importance of Bet Hedging
2018
Adaptive explanations for dormancy often invoke bet hedging, where reduced mean fitness can be adaptive if it associates with reduced fitness variance. Sex allocation theory typically ignores variance effects and focuses on mean fitness. For many cyclical parthenogens, these themes become linked, as only sexually produced eggs undergo the dormancy needed to survive harsh conditions. We ask how sex allocation and the timing of sex evolve when this constraint exists in the form of a trade-off between asexual reproduction and sexual production of dormant eggs—the former being crucial for within-season success and the latter for survival across seasons. We show that male production can be tempo…
Genetic variability of the blue and red shrimp Aristeus antennatus in the Western Mediterranean Sea inferred by DNA microsatellite loci
2012
Genetic variation at eight microsatellite loci was studied in nine populations of the blue and red shrimp Aristeus antennatus to investigate whether distinct stocks are present in the Western Mediterranean Sea. A high level of gene flow and no evidence of genetic partitioning were discovered. No significant variation was found (FST = 0.00673, P-value = 0.067) even when shrimps from exploited and those from deep-water unexploited grounds were compared. No evidence of reduction or expansion of population size in the recent past was found, as indicated by the bottleneck and interlocus g-tests. Our results are consistent with previous studies using mitochondrial gene methods and allozymes, indi…
New Gynandromorph Records for Chirocephalus diaphanus (Branchiopoda, Anostraca, Chirocephalidae)
2021
We report and describe new Chirocephalus diaphanus Prévost, 1803 gynandromorphs from Tunisia and review the literature of anostracan gynandromorphy and other, possibly associated, somatic aberrations, with comments on their evolutionary significance. Our material has three specimens that are specifically deformed on the left side of the head.
Protozooplanktons kā potenciāls indikators pilsētvides hidroekosistēmās
2015
Pētījuma mērķis ir noskaidrot, vai protozooplanktona organismi ir potenciāli pielietojami pilsētvides hidroekosistēmu ekoloģiskā stāvokļa novērtējumam. 2014. gada veģetācijas sezonā analizēti 26 paraugi, kas ievākti reizi mēnesī divos ezeros un divos karjeros. Tika aprēķināta ciliātu biomasa, veikta organismu sezonālās dinamikas un izmēru grupu sadalījuma analīze. Šāda veida pētījumi par pilsētas ūdenskrātuvju novērtēšanu, analizējot protozooplanktonu, ir pirmie Latvijas teritorijā. Nākotnes pētījumos jāiekļauj arī oligotrofi ezeri, lai novērtētu ciliātu izmēru grupu dinamiku, mainoties trofijas līmenim. Bakalaura darbs izstrādāts no 2014. gada augusta līdz 2015. gada maijam Latvijas Univer…
Genomic diversity and population structure analysis reveal few genetic differences among Ethiopian indigenous sheep populations
2017
African sheep, like other domestic sheep, are domesticated from the Asiatic mouflon (Ovis orientalis). They entered the continent through the North and the Horn of Africa regions following maritime and terrestrial trading routes. Ethiopia is one of the main entry points of various plant and animal domesticates into Africa. It is characterised by diverse agro-ecologies, ancient human ethnic diversity and the presence of indigenous sheep breeds/populations of unprecedented morphological diversity (e.g. tail types). Here, we investigate the genome diversity and population structure of 146 unrelated animals from 11 Ethiopian indigenous sheep populations. DNA was extracted from ear tissue punche…