27 research outputs found
Low-frequency signals produced by Northeast Atlantic killer whales (Orcinus orca)
No full textKiller whale acoustic behavior has been extensively investigated, however most studies have focused on pulsed calls and whistles. This study reports the production of low-frequency signals by killer whales at frequencies below 300 Hz. Recordings of killer whales were made in Iceland and Norway when whales were observed feeding on herring, and no other cetacean species were nearby. Low-frequency sounds were identified in Iceland and ranged in duration between 0.14 and 2.77 seconds and in frequency between 50 and 270 Hz, well below the previously reported lower limit for killer whale tonal sounds of 500 Hz. LFS appeared to be produced close in time to tail slaps, indicative of feeding attempts, suggesting that these sounds may be related to a feeding context. However, their precise function is unknown and they could be the by-product of a non-vocal behavior, rather than a vocal signal deliberately produced by the whales. Although killer whales in Norway exhibit similar feeding behavior, this sound was not detected in recordings from Norway. This study suggests that, like other delphinids, killer whales also produce low-frequency sounds but further studies will be required to understand whether similar sounds exist in other killer whale populations
A multilevel society of herring-eating killer whales indicates adaptation to prey characteristics
No full textThis work was supported by the Fundação para a Ciência e a Tecnologia (grant numbers SFSFRH/BD/30303/2006 and SFRH/BD/84714/2012); Icelandic Research Fund (i. Rannsóknasjóđur, grant number 120248402); National Geographic Society Science and Exploration Europe (grant number GEFNE65-12); Office of Naval Research (grant number N00014-08-10984); and a Russell Trust Award from the University of St. Andrews.Non-social factors can influence animal social structure. In killer whales (Orcinus orca), fish- versus mammal-eating ecological differences are regarded as key ecological drivers of their multilevel society, including group size, but the potential importance of specific target prey remains unclear. Here, we investigate the social structure of herring-eating killer whales in Iceland and compare it to the described social structures of primarily salmon- and seal-eating populations in the Northeast Pacific, which form stable coherent basic units nested within a hierarchical multilevel society. Using 29023 photographs collected over 6 years, we examined the association patterns of 198 individuals combining clustering, social network structure, and temporal patterns of association analysis. The Icelandic population had largely weak but non-random associations, which were not completely assorted by known ranging patterns. A fission–fusion dynamic of constant and temporary associations was observed but this was not due to permanent units joining. The population-level society was significantly structured but not in a clear hierarchical tier system. Social clusters were highly diverse in complexity and there were indications of subsclusters. There was no indication of dispersal nor strong sex differences in associations. These results indicate that the Icelandic herring-eating killer whale population has a multilevel social structure without clear hierarchical tiers or nested coherent social units, different from other populations of killer whales. We suggest that local ecological context, such as the characteristics of the specific target prey (e.g., predictability, biomass, and density) and subsequent foraging strategies may strongly influence killer whale social association patterns.Peer reviewe
Association matrix and individual supplementary details of Icelandic killer whales
No full textFirst sheet with details for each individual (sex-age class, movement pattern, number of records - number of photographs -, number of total days sampled and number of different years seen). Second sheet with the association matrix for all individuals, no restrictions on the number of sightings, calculated using SOCPROG 2.6 software (half-weight index used)
Geographic variation in the time-frequency characteristics of high-frequency whistles produced by killer whales (Orcinus orca)
No full textInvestigating intraspecific variation in acoustic signals can indicate the extent of isolation and divergence between populations and adaptations to local environments. Here we analyze the variation in killer whale high frequency (>17 kHz) whistles recorded off Norway, Iceland, and in the North Pacific. We used a combination of methods including multivariate comparisons of spectral and temporal parameters and categorization of contours to types. Our results show that spectral and temporal characteristics of high-frequency whistles recorded in the North Pacific show significant differences from whistles recorded in the Northeast Atlantic, being generally stereotyped, lower in frequency, and slightly longer in duration. Most high-frequency whistles from the North Pacific were downsweeps, whereas this was one of the least common types recorded in the Northeast Atlantic. The repertoire of whistles recorded in Norway was similar to Iceland, but whistles produced in Norway had significantly lower maximum frequency and frequency range. Most methods were able to discriminate between whistles of the North Pacific and the Northeast Atlantic, but were unable to consistently distinguish whistles from Iceland and Norway. This suggests that macro- and microgeographic differences in high-frequency whistles of killer whales may reflect historical geographic isolation between ocean basins and more recent divergence between adjacent populations
Persistence of skin marks on killer whales (Orcinus orca) caused by the parasitic sea lamprey (Petromyzon marinus) in Iceland
No full textLampreys have long been thought to be a cetacean ectoparasite, due to the observation of round marks on the skin of whales caught during whaling operations. Pike (1951), Nemoto (1955), and van Utrecht (1959) compared such marks on the skin of various cetacean species caught in the Pacific and Atlantic Oceans with the dentition of lampreys and concluded that most round marks had been caused by this parasite. However, lampreys were never collected from captured whales and, due to the lack of direct evidence, some discussion emerged as to the origin of these wounds. Jones (1971) later argued that crescent-shaped marks previously attributed to lampreys were in fact caused by cookie-cutter sharks (Isistius brasiliensis). However, he agreed that other round marks were undoubtedly caused by lampreys. Recently, photographs of sea lampreys (Petromyzon marinus) attached to northern right whales, Eubalaena glacialis (Nichols and Hamilton 2004), and minke whales, Balaenoptera acutorostrata (Nichols and Tscherter 2011), in the western North Atlantic conclusively showed that lampreys do associate with those species. Similar evidence for other cetaceans is still lacking
Killer whales (Orcinus orca) in Iceland show weak genetic structure among diverse isotopic signatures and observed movement patterns
No full textFunding was provided by the Fundação para a Ciência e a Tecnologia (grant number SFRH/BD/84714/2012) and a MASTS (The Marine Alliance for Science and Technology for Scotland) pooling initiative (grant reference SG188) funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions to S.B.T. and the Icelandic Research Fund (Rannsóknasjóđur, grant number 120248042) to F.I.P.S.Local adaption through ecological niche specialization can lead to genetic structure between and within populations. In the Northeast Pacific, killer whales (Orcinus orca) of the same population have uniform specialized diets that are non‐overlapping with other sympatric, genetically divergent, and socially isolated killer whale ecotypes. However, killer whales in Iceland show intrapopulation variation of isotopic niches and observed movement patterns: some individuals appear to specialize on herring and follow it year‐round while others feed upon herring only seasonally or opportunistically. We investigated genetic differentiation among Icelandic killer whales with different isotopic signatures and observed movement patterns. This information is key for management and conservation purposes but also for better understanding how niche specialization drives genetic differentiation. Photo‐identified individuals (N = 61) were genotyped for 22 microsatellites and a 611 bp portion of the mitochondrial DNA (mtDNA) control region. Photo‐identification of individuals allowed linkage of genetic data to existing data on individual isotopic niche, observed movement patterns, and social associations. Population subdivision into three genetic units was supported by a discriminant analysis of principal components (DAPC). Genetic clustering corresponded to the distribution of isotopic signatures, mtDNA haplotypes, and observed movement patterns, but genetic units were not socially segregated. Genetic differentiation was weak (FST < 0.1), suggesting ongoing gene flow or recent separation of the genetic units. Our results show that killer whales in Iceland are not as genetically differentiated, ecologically discrete, or socially isolated as the Northeast Pacific prey‐specialized killer whales. If any process of ecological divergence and niche specialization is taking place among killer whales in Iceland, it is likely at a very early stage and has not led to the patterns observed in the Northeast Pacific.Peer reviewe
Cultural evolution of killer whale calls: background, mechanisms and consequences
No full textCultural evolution is a powerful process shaping behavioural phenotypes of many species including our own. Killer whales are one of the species with relatively well-studied vocal culture. Pods have distinct dialects comprising a mix of unique and shared call types; calves adopt the call repertoire of their matriline through social learning. We review different aspects of killer whale acoustic communication to provide insights into the cultural transmission and gene-culture co- evolution processes that produce the extreme diversity of group and population repertoires. We argue that the cultural evolution of killer whale calls is not a random process driven by steady error accumulation alone: temporal change occurs at different speeds in different components of killer whale repertoires, and constraints in call structure and horizontal transmission often degrade the phylogenetic signal. We discuss the implications from bird song and human linguistic studies, and propose several hypotheses of killer whale dialect evolution
Killer whales (Orcinus orca) produce ultrasonic whistles
No full textThis study reports that killer whales, the largest dolphin, produce whistles with the highest fundamental frequencies ever reported in a delphinid. Using wide-band acoustic sampling from both animal-attached (Dtag) and remotely deployed hydrophone arrays, ultrasonic whistles were detected in three Northeast Atlantic populations but not in two Northeast Pacific populations. These results are inconsistent with analyses suggesting a correlation of maximum frequency of whistles with body size in delphinids, indicate substantial intraspecific variation in whistle production in killer whales, and highlight the importance of appropriate acoustic sampling techniques when conducting comparative analyses of sound repertoires
Plantas medicinais e a sua relevância nos processos oxidativos e inflamatórios
No full textPrograma doutoral em Agricultural Production Chains – From Fork to Farm (Agrichains)As plantas aromáticas e medicinais têm sido uma parte integrante da civilização humana desde a
antiguidade, como terapias para várias doenças e contribuindo para o desenvolvimento da medicina
tradicional em todo o mundo. Estas plantas contêm uma diversidade de compostos bioativos com
propriedades terapêuticas, tornando-as recursos valiosos para as indústrias da saúde e farmacêutica.
Com o crescente interesse em abordagens naturais e holísticas, o estudo e a utilização de plantas
aromáticas e medicinais continuam a atrair a atenção de investigadores, profissionais de saúde e
consumidores.
Este trabalho teve como objetivo a valorização das plantas medicinais e aromáticas, com um foco
específico nas Coreopsis tinctoria, Baccharis dracunculifolia e Genista tridentata. Ao aumentar a
consciencialização sobre o seu potencial como fontes de compostos bioativos com valor medicinal e
económico significativo, procurámos identificar extratos que exibam atividades bioativas empregáveis nas
indústrias farmacêutica, alimentar e cosmética.
Demonstramos que os extratos das plantas estudadas (C. tinctoria, B. dracunculifolia e G. tridentata)
possuem um elevado teor de compostos fenólicos, os quais contribuem para as suas fortes atividades
antioxidantes no sequestro de radicais livres, antinociceptivas em modelos experimentais de osteoartrose
e diabetes tipo 2, assim como atividades anti-inflamatórias em modelos de irritação dérmica e de feridas
em animais diabéticos. Assim, estes resultados apoiam a utilização destas plantas em formulações
farmacêuticas ou como ingredientes alimentares funcionais. A interação sinérgica entre plantas
medicinais e terapias convencionais revela-se promissor para melhorar a eficácia de tratamentos pré-existentes e reduzir efeitos colaterais.Aromatic and medicinal plants have been an integral part of human civilization since ancient times,
providing therapies for various diseases and contributing to the development of traditional medicine
worldwide. These plants contain a diverse array of bioactive compounds with therapeutic properties,
making them valuable resources for the healthcare and pharmaceutical industries. With the growing
interest in natural and holistic approaches, the study and use of aromatic and medicinal plants continues
to attract the attention of researchers, healthcare professionals and consumers.
This work aimed to highlight the valorization of medicinal and aromatic plants, with a specific focus on
Coreopsis tinctoria, Baccharis dracunculifolia and Genista tridentata. By raising awareness of their
potential as sources of bioactive compounds with significant medicinal and economic value, we sought
to identify extracts that exhibit bioactive activities applicable acrossthe pharmaceutical, food and cosmetic
industries.
Our findings demonstrate the extracts of the studied plants (C. tinctoria, B. dracunculifolia and G.
tridentata) have a rich phenolic compounds content, which contribute to their strong antioxidant activities
in free radical scavenging, analgesic activities in experimental models of osteoarthritis and type 2
diabetes, as well as anti-inflammatory activities in models of dermal irritation and diabetic-induced
wounds. Thus, these results support the use of these plants in pharmaceutical formulations or as
functional food ingredients. The synergistic interaction between medicinal plants and conventional
therapies shows promise for improving the efficacy of pre-existing treatments and reducing side effects.The author Inês Martins Laranjeira acknowledges the financial support provided by the FCT-Portuguese
Foundation for Science and Technology (PD/BD/150263/2019 and COVID/BD/153324/2023) under
the Doctoral Program "Agricultural Production Chains from fork to farm" (PD/00122/2012) and from
the European Social Funds and the Regional Operational Programme Norte 2020. Furthermore, this work
received support from the European Investment Funds FEDER/COMPETE/POCI – Operational
Competitiveness and Internationalization Programme [POCI-01-0145-FEDER-031987], as well as the
Portuguese Foundation for Science and Technology (FCT) [UIDB/50026/2020 and UIDP/50026/2020].
Additionally, the research was backed by Financiamento Plurianual de Unidades de I&D UIDB/04, and
"Contrato-Programa" UIDB/04033/2020 and UIDB/04050/2020 funded by national funds of the FCT
I.P
A worldwide analysis
No full textFunding Information: This article was supported by National Funds through FCT—Fundação para a Ciência e a Tecnologia,I.P., within CINTESIS, R&D Unit (reference UIDP/4255/2020). JP received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No.721402. Funding Information: The authors acknowledge FCT—Fundação para a Ciência e a Tecnologia,I.P. and the European Research Council (ERC) for the funding. This article was supported by National Funds through FCT - Fundação para a Ciência e a Tecnologia,I.P., within CINTESIS, R&D Unit (reference UIDP/4255/2020). Publisher Copyright: © 2023, The Author(s).Introduction: Healthcare expenditure, a common input used in health systems efficiency analyses is affected by population age structure. However, while age structure is usually considered to adjust health system outputs, health expenditure and other inputs are seldom adjusted. We propose methods for adjusting Health Expenditure per Capita (HEpC) for population age structure on health system efficiency analyses and assess the goodness-of-fit, correlation, reliability and disagreement of different approaches. Methods: We performed a worldwide (188 countries) cross-sectional study of efficiency in 2015, using a stochastic frontier analysis. As single outputs, healthy life expectancy (HALE) at birth and at 65 years-old were considered in different models. We developed five models using as inputs: (1) HEpC (unadjusted); (2) age-adjusted HEpC; (3) HEpC and the proportion of 0–14, 15–64 and 65 + years-old; (4) HEpC and 5-year age-groups; and (5) HEpC ageing index. Akaike and Bayesian information criteria, Spearman’s rank correlation, intraclass correlation coefficient and information-based measure of disagreement were computed. Results: Models 1 and 2 showed the highest correlation (0.981 and 0.986 for HALE at birth and HALE at 65 years-old, respectively) and reliability (0.986 and 0.988) and the lowest disagreement (0.011 and 0.014). Model 2, with age-adjusted HEpC, presented the lowest information criteria values. Conclusions: Despite different models showing good correlation and reliability and low disagreement, there was important variability when age structure is considered that cannot be disregarded. The age-adjusted HE model provided the best goodness-of-fit and was the closest option to the current standard.publishe
