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1.
Science ; 367(6475): 249, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31949068
2.
Nature ; 577(7791): 458-459, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31965097
3.
Ecol Lett ; 23(3): 537-544, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31943670

RESUMO

While the anthropogenic impact on ecosystems today is evident, it remains unclear if the detrimental effect of hominins on co-occurring biodiversity is a recent phenomenon or has also been the pattern for earlier hominin species. We test this using the East African carnivore fossil record. We analyse the diversity of carnivores over the last four million years and investigate whether any decline is related to an increase in hominin cognitive capacity, vegetation changes or climatic changes. We find that extinction rates in large carnivores correlate with increased hominin brain size and with vegetation changes, but not with precipitation or temperature changes. While temporal analyses cannot distinguish between the effects of vegetation changes and hominins, we show through spatial analyses of contemporary carnivores in Africa that only hominin causation is plausible. Our results suggest that substantial anthropogenic influence on biodiversity started millions of years earlier than currently assumed.


Assuntos
Hominidae , África , África Oriental , Animais , Encéfalo , Ecossistema , Fósseis
4.
Ecol Lett ; 23(3): 439-446, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31854097

RESUMO

Leigh Van Valen famously stated that under constant conditions extinction probability is independent of species age. To test this 'law of constant extinction', we developed a new method using deep learning to infer age-dependent extinction and analysed 450 myr of marine life across 21 invertebrate clades. We show that extinction rate significantly decreases with age in > 90% of the cases, indicating that most species died out soon after their appearance while those which survived experienced ever decreasing extinction risk. This age-dependent extinction pattern is stronger towards the Equator and holds true when the potential effects of mass extinctions and taxonomic inflation are accounted for. These results suggest that the effect of biological interactions on age-dependent extinction rate is more intense towards the tropics. We propose that the latitudinal diversity gradient and selection at the species level account for this exceptional, yet little recognised, macroevolutionary and macroecological pattern.


Assuntos
Biodiversidade , Extinção Biológica , Animais , Evolução Biológica , Fósseis , Invertebrados
5.
Syst Biol ; 69(1): 1-16, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31058981

RESUMO

Establishing an accurate evolutionary timescale for green plants (Viridiplantae) is essential to understanding their interaction and coevolution with the Earth's climate and the many organisms that rely on green plants. Despite being the focus of numerous studies, the timing of the origin of green plants and the divergence of major clades within this group remain highly controversial. Here, we infer the evolutionary timescale of green plants by analyzing 81 protein-coding genes from 99 chloroplast genomes, using a core set of 21 fossil calibrations. We test the sensitivity of our divergence-time estimates to various components of Bayesian molecular dating, including the tree topology, clock models, clock-partitioning schemes, rate priors, and fossil calibrations. We find that the choice of clock model affects date estimation and that the independent-rates model provides a better fit to the data than the autocorrelated-rates model. Varying the rate prior and tree topology had little impact on age estimates, with far greater differences observed among calibration choices and clock-partitioning schemes. Our analyses yield date estimates ranging from the Paleoproterozoic to Mesoproterozoic for crown-group green plants, and from the Ediacaran to Middle Ordovician for crown-group land plants. We present divergence-time estimates of the major groups of green plants that take into account various sources of uncertainty. Our proposed timeline lays the foundation for further investigations into how green plants shaped the global climate and ecosystems, and how embryophytes became dominant in terrestrial environments.


Assuntos
Evolução Biológica , Classificação/métodos , Fósseis , Viridiplantae/classificação , Genoma de Cloroplastos/genética , Tempo , Viridiplantae/genética
6.
Syst Biol ; 69(1): 124-138, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31127936

RESUMO

Timescales are of fundamental importance to evolutionary biology as they facilitate hypothesis tests of historical evolutionary processes. Through the incorporation of fossil occurrence data, the fossilized birth-death (FBD) process provides a framework for estimating divergence times using more paleontological data than traditional node calibration approaches have allowed. The inclusion of more data can refine evolutionary timescale estimates, but for many taxonomic groups it is computationally infeasible to include all available fossil occurrence data. Here, we utilize both empirical data and a simulation framework to identify approaches to subsampling fossil occurrence data that result in the most accurate estimates of divergence times. To achieve this we assess the performance of the FBD-Skyline model when implementing multiple approaches to incorporating subsampled fossil occurrence data. Our results demonstrate that it is necessary to account for all available fossil occurrence data to achieve the most accurate estimates of clade age. We show that this can be achieved if an empirical Bayes approach, accounting for fossil sampling through time, is applied to the FBD process. Random subsampling of occurrence data can lead to estimates of clade age that are incompatible with fossil evidence if no control over the affinities of fossil occurrences is enforced. Our results call into question the accuracy of previous divergence time studies incorporating the FBD process that have used only a subsample of all available fossil occurrence data.


Assuntos
Evolução Biológica , Classificação/métodos , Fósseis , Modelos Biológicos
7.
Nature ; 576(7785): 44-45, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31792418
8.
Biol Lett ; 15(12): 20190622, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31795849

RESUMO

There has been much discussion over whether basal birds (e.g. Archaeopteryx and Confuciusornis) exhibited active flight. A recent study of barb angles has suggested they likely could not but instead may have exhibited a gliding phase. Pennaceous primary flight feathers were proposed to show significant shifts in barb angle values of relevance to the inference of flight in these extinct taxa. However, evolutionary trends in the evolution of these barb angle traits in extant volant taxa were not analysed in a phylogenetic frame. Neither the ancestral crown avian condition nor the condition in outgroup dinosaurs with symmetrical feathers were assessed. Here, we expand the fossil sample and reanalyse these data in a phylogenetic frame. We show that extant taxa, including strong flyers (e.g. some songbirds), show convergence on trailing barb angles and barb angle asymmetry observed in Mesozoic taxa that were proposed not to be active fliers. Trailing barb angles in these Mesozoic taxa are similar to symmetrical feathers in outgroup dinosaurs, indicating that selective regimes acted to modify primarily the leading-edge barb angles. These trends inform dynamics in feather shape evolution and challenge the notion that barb angle and barb angle ratios in extant birds directly inform the reconstruction of function in extinct stem taxa.


Assuntos
Dinossauros , Animais , Evolução Biológica , Aves , Plumas , Voo Animal , Fósseis , Filogenia
9.
BMC Evol Biol ; 19(1): 213, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752661

RESUMO

BACKGROUND: Dispersal is essential for terrestrial organisms living in disjunct habitats and constitutes a significant challenge for the evolution of wingless taxa. Springtails (Collembola), the sister-group of all insects (with Diplura), are reported since the Lower Devonian and are thought to have originally been subterranean. The order Symphypleona is reported since the early Cretaceous with genera distributed on every continent. This distribution implies an ability to disperse over oceans, however symphypleonan Collembola have never been reported in marine water contrary to other springtail orders. Despite being highly widespread, modern springtails are rarely reported in any kind of biotic association. Interestingly, the fossil record has provided occasional occurrences of Symphypleona attached by the antennae onto the bodies of larger arthropods. RESULTS: Here, we document the case of a ~ 16 Ma old fossil association: a winged termite and ant displaying not some, but 25 springtails attached or in close proximity to the body. The collembola exhibit rare features for fossils, reflecting their courtship and phoretic behaviours. By observing the modes of attachment of springtails on different arthropods, the sex representation and ratios in springtail antennal anatomies in new and previously reported cases, we infer a likely mechanism for dispersal in Symphypleona. By revealing hidden evidence of modern springtail associations with other invertebrates such as ants and termites, new compelling assemblages of fossil springtails, and the drastic increase of eusocial insects' abundance during the Cenozoic (ants/termites comprising more than a third of insects in Miocene amber), we stress that attachment on winged castes of ants and termites may have been a mechanism for the worldwide dispersal of this significant springtail lineage. Moreover, by comparing the general constraints applying to the other wingless soil-dwelling arthropods known to disperse through phoresy, we suggest biases in the collection and observation of phoretic Symphypleona related to their reflexive detachment and infer that this behaviour continues today. CONCLUSIONS: The specific case of tree resin entrapment represents the (so far) only condition uncovering the phoretic dispersal mechanism of springtails - one of the oldest terrestrial arthropod lineages living today.


Assuntos
Artrópodes/anatomia & histologia , Artrópodes/fisiologia , Fósseis , Âmbar , Animais , Formigas , Artrópodes/classificação , Evolução Biológica , Ecossistema , Isópteros , Masculino , Solo
10.
Nat Commun ; 10(1): 4778, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31699998

RESUMO

The divergence of crown catarrhines-i.e., the split of cercopithecoids (Old World monkeys) from hominoids (apes and humans)-is a poorly understood phase in our shared evolutionary history with other primates. The two groups differ in the anatomy of the hip joint, a pattern that has been linked to their locomotor strategies: relatively restricted motion in cercopithecoids vs. more eclectic movements in hominoids. Here we take advantage of the first well-preserved proximal femur of the early Oligocene stem catarrhine Aegyptopithecus to investigate the evolution of this anatomical region using 3D morphometric and phylogenetically-informed evolutionary analyses. Our analyses reveal that cercopithecoids and hominoids have undergone divergent evolutionary transformations of the proximal femur from a similar ancestral morphology that is not seen in any living anthropoid, but is preserved in Aegyptopithecus, stem platyrrhines, and stem cercopithecoids. These results highlight the relevance of fossil evidence for illuminating key adaptive shifts in primate evolution.


Assuntos
Membro Posterior , Animais , Evolução Biológica , Cercopithecidae , Fósseis , Hominidae , Humanos , Filogenia
11.
Zootaxa ; 4612(3): zootaxa.4612.3.13, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31717062

RESUMO

In oceanic islands, well age-constrained deposits containing arthropod somatofossils (body fossils) are rare. However, when available, these are important for providing empirical and independent minimum ages for molecular phylogenetic dating and complementary data on taxonomy, evolution and palaeobiogeography information of the biological groups found as fossils. This is especially important for taxa that speciated within oceanic islands, many becoming single island endemics (SIE). Recently, associated with a 1.3 Ma (Calabrian) fluvial and lacustrine sedimentary deposit from Porto da Cruz in Madeira Island (Fig. 1), a wing, putatively identified as Hymenoptera, was found. Here we describe this wing fossil as belonging to Ichneumonidae, a group with ca. 30% of SIE in Madeira Island. Moreover, this is the first somatofossil of ichneumonid parasitic wasps found in Madeira Island and in Macaronesian islands (i.e. Azores, Madeira, Canaries and Cabo Verde).


Assuntos
Fósseis , Animais , Açores , Cabo Verde , Filogenia , Portugal
12.
Zootaxa ; 4609(3): zootaxa.4609.3.13, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31717103

RESUMO

In this paper, we describe a new genus and species of soldier beetles from Burmese amber, Elektrokleinia picta gen. et. sp. nov., characterized by triangular shape of the head behind the eyes, by the elytra not covering two urites and the last urite being concave at its apex. Additionally, this new specimen shows remarkable color preservation (black-blue) on the elytra, rarely present in amber or seen on fossil soldier beetles. This coloration with metallic nuances is here considered an aposematic character.


Assuntos
Âmbar , Besouros , Animais , Cor , Olho , Fósseis
13.
Zootaxa ; 4609(1): zootaxa.4609.1.12, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31717128

RESUMO

Notaepytus quisqueya sp. nov. (Erotylidae: Erotylinae: Tritomini), is described here from Dominican amber and is the second amber fossil description for the family from the West Indies (Hispaniola). An emended key and a checklist to all known species of Notaepytus are presented.


Assuntos
Besouros , Âmbar , Animais , República Dominicana , Fósseis , Índias Ocidentais
14.
Zootaxa ; 4604(3): zootaxa.4604.3.4, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31717178

RESUMO

A new genus of the family Callianassidae, Laticallichirus, is established for "Neocallichirus" grandis Karasawa Goda, 1996, a ghost shrimp species heretofore represented only by fossil materials from the middle to upper Pleistocene of Japan. The newly collected specimens came from two Japanese localities: Numazu, Shizuoka Prefecture (Suruga Bay) and Tosa, Kochi Prefecture (Tosa Bay), included within the known geographical range derived from fossil records. The species identification was based on the close agreement in the cheliped morphology and the known fossil distributions. The new genus is assigned to the subfamily Callichirinae Manning Felder, 1991, and compared with seven genera, Balsscallichirus Sakai, 2011, Callichirus Stimpson, 1866, Callichiropsis Sakai, 2010, Grynaminna Poore, 2000, Michaelcallianassa Sakai, 2002, Lepidophthalmus Holmes, 1904 and Podocallichirus Sakai, 1999, all characterized by the antennular peduncle being longer and stouter than the antennal peduncle. The new genus is characteristic in combination of the following characters: rostrum spiniform; maxilliped 3 devoid of exopod; ischium-merus of maxilliped 3 broadly operculiform; maxilliped 3 ischium devoid of crista dentata; major cheliped devoid of meral hook or associated lobe-like structure; tergites of the pleomeres 3-5 without conspicuous ornamentation; male pleopod 2 biramous, its endopod devoid of appendices interna and masculina; uropodal endopod suboval in shape; telson distinctly wider than long, with shallowly concave posterior margin. The genetic analysis using the mitochondrial 16S rRNA places the new genus as sister to Callichirus Stimpson, 1866, although bootstrap support for major branches is generally low. The newly collected specimens were found in burrows in soft sediments of shallow subtidal zone being accessible at low tide.


Assuntos
Fósseis , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , Japão , Quênia , Masculino , Tamanho do Órgão , RNA Ribossômico 16S
15.
Zootaxa ; 4603(2): zootaxa.4603.2.7, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717231

RESUMO

Four new genera and five new species of anaxyelids are described from the Cretaceous of Asia: Mangus magnus gen. et sp. nov. from the Aptian of Mongolia (Bon-Tsagan), Urosyntexis undosa sp. nov., Parasyntexis khasurtensis gen. et sp. nov., both from the Early Cretaceous of Transbaikalia (Khasurty), Dolichosyntexis transbaikalicus gen. et sp. nov. from the Hauterivian-Barremian of Transbaikalia (Baissa), and Curiosyntexis magadanicus gen. et sp. nov. from the mid-Upper Cretaceous of NE Siberia (Obeshchayushchiy). Early Cretaceous is the time of the highest diversity of Anaxyelidae. In this epoch these sawflies are represented with all four subfamilies comprising the group. In Late Cretaceous anaxyelid diversity and abundance rapidly decrease and they are represented with the only subfamily Syntexinae. The anaxyelid collection of Palaeontological Institute (Moscow), the most representative collection of fossil anaxyelids in the world, has been completely revised, identified and described. The list of identifications is provided.


Assuntos
Himenópteros , Animais , Ásia , Fósseis , Mongólia , Moscou , Sibéria
16.
Zootaxa ; 4691(2): zootaxa.4691.2.4, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31719403

RESUMO

A new genus and species of rhagionids with a long proboscis, Elliprhagio macrosiphonius gen. et sp. nov., is described from the Middle Jurassic Jiulongshan Formation in Daohugou, Inner Mongolia, China, which is considered to be the earliest hematophagous rhagionid described hitherto according to the typically piercing and sucking mouthparts. All previously documented rhagionids from northeastern China are reviewed a key to genera of Rhagionidae from Daohugou is provided for the first time. The genus Daohugorhagio Zhang, 2013 is considered as a new synonym of Trichorhagio Zhang, 2013.


Assuntos
Charadriiformes , Dípteros , Animais , China , Fósseis
17.
Zootaxa ; 4691(1): zootaxa.4691.1.10, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31719419

RESUMO

Sycoracinae is a subfamily of Psychodidae, currently with 45 extant species (Curler Jacobson 2012; Santos et al. 2013) classified in three genera: Sycorax Haliday in Curtis; Parasycorax Duckhouse and Aposycorax Duckhouse (Duckhouse 1972; Young 1979). Sycorax comprises a majority of this diversity with 40 extant species, 15 of which are recorded from the Neotropical region (Curler Jacobson 2012; Santos et al. 2013). Four fossil species of Sycorax have also been described (Curler Jacobson 2012), including one from middle Miocene Amazonian amber (Petrulevicius et al. 2011). In contrast, Parasycorax includes only four extant species; three from South America and one from the Philippines (Santos et al. 2009) and a fossil species from Cretaceous Burmese amber (Stebner et al. 2015). Here we describe a new species of Parasycorax and provide an updated key to males of all extant and fossil species of the genus. In addition, Sycorax bravoi Santos, Ferreira Falqueto and Sycorax espiritosantensis Santos Bravo are recorded for Santa Catarina State, southern Brazil.


Assuntos
Psychodidae , Âmbar , Animais , Brasil , Fósseis , Masculino , Filipinas
18.
Zootaxa ; 4688(4): zootaxa.4688.4.5, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31719428

RESUMO

Four new fossil species of haematophagous biting midges of the genus Culicoides Latreille, from mid-Cretaceous Burmese amber are described and illustrated: C. bojarskii Szadziewski Dominiak sp. nov., C. burmiticus Szadziewski Dominiak sp. nov., C. ellenbergeri Szadziewski Dominiak sp. nov. and C. myanmaricus Szadziewski Dominiak sp. nov. These extinct species are assigned to the new subgenus, Groganomyia Szadziewski Dominiak subgen. nov. which also includes an extant species that inhabits European mountains, Culicoides cameroni Campbell Pelham-Clinton, 1960, the type species. These very old (99 Ma) haematophagous biting midges of the extant genus Culicoides from Burmese amber supports the hypothesis that most groups of modern biting midges evolved during the mid-Cretaceous greenhouse climate.


Assuntos
Ceratopogonidae , Âmbar , Animais , Fósseis
19.
Zootaxa ; 4688(1): zootaxa.4688.1.2, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31719457

RESUMO

Prolachlanius resinatus (Hagen) is re-described, based on five specimens from late Eocene Baltic amber (including the neotype designated herein) and the first recorded specimen from contemporaneous Rovno amber (Klesov locality). This is the most common species of Hemerobiidae in Baltic amber. The forewing venation of Prolachlanius is most similar to that of Sympherobius, and, therefore, its assignment to Sympherobiinae is confirmed. The genus differs from other Sympherobiinae by the distal branch of RP being not deeply forked, and the presence of crossvein 4r-m in the forewing. The male genitalia of Prolachlanius are sufficiently dissimilar from those of other Sympherobiinae to distinguish it as a separate genus, particularly by the structure of the ectoprocts, and the 8th and 9th sternites. The extremely short eighth sternite of Prolachlanius is especially noteworthy.


Assuntos
Âmbar , Fósseis , Animais , Países Bálticos , Holometábolos , Masculino
20.
Zootaxa ; 4686(3): zootaxa.4686.3.5, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31719480

RESUMO

A nomenclature for the family Sphyraenidae is constructed using genus-group and species-group names from both extant and extinct taxa. The Sphyraenidae is found to contain only two genera: The monotypic †Parasphyraena, and Sphyraena. "Sphyraena" amici and "Sphyraena" viennensis are retained in the genus Sphyraena pending a reassessment of their relationships. Although currently allocated out of the Sphyraenidae, the genus †Hypsodon is found to present a problematic status with respect to other fossil genera such as †Pachyrhizodus. Sphyraena intermedia Pastore is found to be a primary homonym of †Sphyraena intermedia Bassani and therefore deemed unavailable and invalid. The ambiguities of collective, otolith-based names are discussed in the context of Sphyraena hansfuchsi, the only species of the family based on otoliths. Fifty-three valid species of Sphyraena are recognized, 28 extant and 25 extinct. Comments on the usefulness of a subgeneric classification for the largest genus, Sphyraena, are made in the context of our current knowledge of their interrelationships.


Assuntos
Fósseis , Perciformes , Animais , Peixes , Membrana dos Otólitos
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