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1.
Biomimetics (Basel) ; 8(4)2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37622967

RESUMO

Effective bioinspiration requires dialogue between designers and biologists, and this dialogue must be rooted in a shared scientific understanding of living systems. To support learning from "nature's overarching design lessons" the Biomimicry Institute has produced ten "Unifying Patterns of Nature". These patterns have been developed to engage with those interested in finding biologically inspired solutions to human challenges. Yet, although well-intentioned and appealing, they are likely to dishearten biologists. The aim of this paper is to identify why and propose alternative principles based on evolutionary theory.

2.
Mar Biol ; 170(4): 47, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968429

RESUMO

Fatty acids and carotenoids are known to have roles in embryonic and larval development of sea cucumbers, but their changes in gonads during gametogenesis have not yet been studied. To improve our knowledge of the reproductive cycle of sea cucumbers in an aquaculture perspective, we collected 6-11 individuals of the species Holothuria (Panningothuria) forskali Delle Chiaje, 1823 approximately every 2 months from December 2019 to July 2021 east of the Glenan Islands (Brittany - France; 47.710°N, 3.948°W) at a depth of 8-12 m. Our results show that soon after spawning, sea cucumbers take advantage of an increased food availability in spring to rapidly and opportunistically accumulate nutrients in the form of lipids in their gonads (from May to July) and then slowly elongate, desaturate and probably rearrange fatty acids within lipid classes for the next reproductive season according to the specific requirements of both sexes. In contrast, acquisition of carotenoids occurs synchronously with gonads filling and/or through the reabsorption of spent tubules (T5), thus revealing little seasonal variations at the scale of the entire gonad in terms of relative abundance in both sexes. All results suggest that gonads are fully replenished with nutrients by October and that broodstock for induced reproduction could be captured at this moment and kept until the production of larvae is required. Maintaining broodstock for consecutive years would probably be a higher level challenge as the dynamics of tubule recruitment are not fully understood and seem to last for several years. Supplementary Information: The online version contains supplementary material available at 10.1007/s00227-023-04198-0.

3.
Zootaxa ; 4560(1): 51-84, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30790991

RESUMO

The genus Conocrinus d'Orbigny, 1850 (Crinoidea, Bourgueticrinina) was established on the basis of two aboral cups that had previously been described as Bourgueticrinus thorenti d'Archiac, 1846. One of these (now considered lost) came from the "Rocher du Goulet" at the base of the Biarritz section (Bartonian, Côte des Basques, southwest France). D'Archiac figured only the second cup; this belongs to the d'Orbigny Collection and is still housed in the palaeontological collection of the Muséum national d'Histoire naturelle (Paris) as the lectotype of the species, C. thorenti. It appears that it was collected from Priabonian levels exposed near Castellane (Alpes de Haute Provence, southeast France). New observations on this cup, as well as a detailed study of the characters of aboral cups, columnals and proximal brachials in a few extant and fossil species classically attributed to Conocrinus or to closely related genera such as Democrinus, Rhizocrinus and Tormocrinus, have yielded arguments for a revision of the taxonomy and interrelationships of extant and fossil taxa in the family Bourgueticrinidae. Conocrinus (= Tormocrinus), as here interpreted, includes six Eocene species: C. thorenti, C. archiaci, C. cahuzaci n. sp., C. duperrieri, C. cf. suessi and C. veronensis. Numerous extinct species previously attributed to Conocrinus or Democrinus are here transferred to two new genera which first occur in the lower Paleocene: Paraconocrinus n. gen. (type species: P. pyriformis) and Pseudoconocrinus n. gen. (type species: P. doncieuxi). Aboral cups from the "Rocher du Goulet" (Biarritz) are here assigned to Paraconocrinus pellati n. gen., n. sp., while the Danian species Democrinus maximus is transferred to Pseudoconocrinus n. gen. A new genus, Cherbonniericrinus, is created to accommodate a single extant species, Ch. cherbonnieri, previously attributed to Conocrinus, while the extant genus Rhizocrinus, closely related to Democrinus, is resurrected. Conocrinus and closely related genera are derived from a bourgueticrinine lineage the first record of which is from the lower Campanian, with the new genus Carstenicrinus. These are all attributed to the family Rhizocrinidae which is here considered distinct from the family Bourgueticrinidae. Rhizocrinids rapidly diversified immediately after the Cretaceous-Paleogene (K/Pg) event. Cretaceous taxa previously placed within the family Bourgueticrinidae now appear to be polyphyletic. Some of them do not belong to Bourgueticrinina, such as those of the Dunnicrinus lineage. Interrelationships of Rhizocrinidae and other post-Palaeozoic families having a xenomorphic stalk are discussed.


Assuntos
Equinodermos , Fósseis , Animais , França , Paris , Espanha
4.
Zookeys ; (747): 141-156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29674908

RESUMO

The present dataset is a compilation of georeferenced occurrences of asteroids (Echinodermata: Asteroidea) in the Southern Ocean. Occurrence data south of 45°S latitude were mined from various sources together with information regarding the taxonomy, the sampling source and sampling sites when available. Records from 1872 to 2016 were thoroughly checked to ensure the quality of a dataset that reaches a total of 13,840 occurrences from 4,580 unique sampling events. Information regarding the reproductive strategy (brooders vs. broadcasters) of 63 species is also made available. This dataset represents the most exhaustive occurrence database on Antarctic and Sub-Antarctic asteroids.

5.
Biol Rev Camb Philos Soc ; 93(1): 481-504, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28799256

RESUMO

Species flocks (SFs) fascinate evolutionary biologists who wonder whether such striking diversification can be driven by normal evolutionary processes. Multiple definitions of SFs have hindered the study of their origins. Previous studies identified a monophyletic taxon as a SF if it displays high speciosity in an area in which it is endemic (criterion 1), high ecological diversity among species (criterion 2), and if it dominates the habitat in terms of biomass (criterion 3); we used these criteria in our analyses. Our starting hypothesis is that normal evolutionary processes may provide a sufficient explanation for most SFs. We thus clearly separate each criterion and identify which biological (intrinsic) and environmental (extrinsic) traits are most favourable to their realization. The first part focuses on evolutionary processes. We highlight that some popular putative causes of SFs, such as key innovations or ecological speciation, are neither necessary nor sufficient to fulfill some or all of the three criteria. Initial differentiation mechanisms are diverse and difficult to identify a posteriori because a primary differentiation of one type (genetic, ecological or geographical) often promotes other types of differentiation. Furthermore, the criteria are not independent: positive feedbacks between speciosity and ecological diversity among species are expected whatever the initial cause of differentiation, and ecological diversity should enhance habitat dominance at the clade level. We then identify intrinsic and extrinsic factors that favour each criterion. Low dispersal emerges as a convincing driver of speciosity. Except for a genomic architecture favouring ecological speciation, for which assessment is difficult, high effective population sizes are the single intrinsic factor that directly enhances speciosity, ecological diversity and habitat dominance. No extrinsic factor appeared to enhance all criteria simultaneously but a combination of factors (insularity, fragmentation and environmental stability) may favour the three criteria, although the effect is indirect for habitat dominance. We then apply this analytical framework to Antarctic marine environments by analysing data from 18 speciose clades belonging to echinoderms (five unrelated clades), notothenioid fishes (five clades) and peracarid crustaceans (eight clades). Antarctic shelf environments and history appear favourable to endemicity and speciosity, but not to ecological specialization. Two main patterns are distinguished among taxa. (i) In echinoderms, many brooding, species-rich and endemic clades are reported, but without remarkable ecological diversity or habitat dominance. In these taxa, loss of the larval stage is probably a consequence of past Antarctic environmental factors, and brooding is suggested to be responsible for enhanced allopatric speciation (via dispersal limitation). (ii) In notothenioids and peracarids, many clades fulfill all three SF criteria. This could result from unusual features in fish and crustaceans: chromosome instability and key innovations (antifreeze proteins) in notothenioids, ecological opportunity in peracarids, and a genomic architecture favouring ecological speciation in both groups. Therefore, the data do not support our starting point that normal evolutionary factors or processes drive SFs because in these two groups uncommon intrinsic features or ecological opportunity provide the best explanation. The utility of the three-criterion SF concept is therefore questioned and guidelines are given for future studies.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Evolução Biológica , Animais , Regiões Antárticas , Ecossistema , Oceanos e Mares , Especificidade da Espécie
6.
PLoS One ; 8(8): e68787, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936311

RESUMO

There has been a significant body of literature on species flock definition but not so much about practical means to appraise them. We here apply the five criteria of Eastman and McCune for detecting species flocks in four taxonomic components of the benthic fauna of the Antarctic shelf: teleost fishes, crinoids (feather stars), echinoids (sea urchins) and crustacean arthropods. Practical limitations led us to prioritize the three historical criteria (endemicity, monophyly, species richness) over the two ecological ones (ecological diversity and habitat dominance). We propose a new protocol which includes an iterative fine-tuning of the monophyly and endemicity criteria in order to discover unsuspected flocks. As a result nine « full ¼ species flocks (fulfilling the five criteria) are briefly described. Eight other flocks fit the three historical criteria but need to be further investigated from the ecological point of view (here called "core flocks"). The approach also shows that some candidate taxonomic components are no species flocks at all. The present study contradicts the paradigm that marine species flocks are rare. The hypothesis according to which the Antarctic shelf acts as a species flocks generator is supported, and the approach indicates paths for further ecological studies and may serve as a starting point to investigate the processes leading to flock-like patterning of biodiversity.


Assuntos
Biodiversidade , Evolução Biológica , Peixes/fisiologia , Animais , Regiões Antárticas , Ecologia , Ecossistema , Densidade Demográfica
7.
Zookeys ; (315): 55-64, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23878509

RESUMO

This circumpolar dataset of the comatulid (Echinodermata: Crinoidea) Promachocrinus kerguelensis (Carpenter, 1888) from the Southern Ocean, documents biodiversity associated with the specimens sequenced in Hemery et al. (2012). The aim of Hemery et al. (2012) paper was to use phylogeographic and phylogenetic tools to assess the genetic diversity, demographic history and evolutionary relationships of this very common and abundant comatulid, in the context of the glacial history of the Antarctic and Sub-Antarctic shelves (Thatje et al. 2005, 2008). Over one thousand three hundred specimens (1307) used in this study were collected during seventeen cruises from 1996 to 2010, in eight regions of the Southern Ocean: Kerguelen Plateau, Davis Sea, Dumont d'Urville Sea, Ross Sea, Amundsen Sea, West Antarctic Peninsula, East Weddell Sea and Scotia Arc including the tip of the Antarctic Peninsula and the Bransfield Strait. We give here the metadata of this dataset, which lists sampling sources (cruise ID, ship name, sampling date, sampling gear), sampling sites (station, geographic coordinates, depth) and genetic data (phylogroup, haplotype, sequence ID) for each of the 1307 specimens. The identification of the specimens was controlled by an expert taxonomist specialist of crinoids (Marc Eléaume, Muséum national d'Histoire naturelle, Paris) and all the COI sequences were matched against those available on the Barcode of Life Data System (BOLD: http://www.boldsystems.org/index.php/IDS_OpenIdEngine). This dataset can be used by studies dealing with, among other interests, Antarctic and/or crinoid diversity (species richness, distribution patterns), biogeography or habitat / ecological niche modeling. This dataset is accessible through the GBIF network at http://ipt.biodiversity.aq/resource.do?r=proke.

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