scholarly journals Reversed evolution of grazer resistance to cyanobacteria

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jana Isanta-Navarro ◽  
Nelson G. Hairston ◽  
Jannik Beninde ◽  
Axel Meyer ◽  
Dietmar Straile ◽  
...  
Keyword(s):  
Rapid Evolution ◽  
Biodiversity Loss ◽  
Large Lake ◽  
Nutrient Input ◽  
Subsequent Reduction ◽  
Relaxed Selection ◽  
Egg Bank ◽  
Harmful Cyanobacteria ◽  
History Of ◽  
Subsequent Loss

AbstractExploring the capability of organisms to cope with human-caused environmental change is crucial for assessing the risk of extinction and biodiversity loss. We study the consequences of changing nutrient pollution for the freshwater keystone grazer, Daphnia, in a large lake with a well-documented history of eutrophication and oligotrophication. Experiments using decades-old genotypes resurrected from the sediment egg bank revealed that nutrient enrichment in the middle of the 20th century, resulting in the proliferation of harmful cyanobacteria, led to the rapid evolution of grazer resistance to cyanobacteria. We show here that the subsequent reduction in nutrient input, accompanied by a decrease in cyanobacteria, resulted in the re-emergence of highly susceptible Daphnia genotypes. Expression and subsequent loss of grazer resistance occurred at high evolutionary rates, suggesting opposing selection and that maintaining resistance was costly. We provide a rare example of reversed evolution of a fitness-relevant trait in response to relaxed selection.

Marine Metazoan Modern Mass Extinction: Improving Predictions by Integrating Fossil, Modern, and Physiological Data

2019 ◽  
Vol 11 (1) ◽  
pp. 369-390 ◽  
Author(s):  
Piero Calosi ◽  
Hollie M. Putnam ◽  
Richard J. Twitchett ◽  
Fanny Vermandele
Keyword(s):  
Global Change ◽  
Extinction Risk ◽  
Biodiversity Loss ◽  
Marine Ecosystems ◽  
Physiological Data ◽  
Marine Biodiversity ◽  
Global Changes ◽  
History Of ◽  
Extinction Events ◽  
Modern Mass

Evolution, extinction, and dispersion are fundamental processes affecting marine biodiversity. Until recently, studies of extant marine systems focused mainly on evolution and dispersion, with extinction receiving less attention. Past extinction events have, however, helped shape the evolutionary history of marine ecosystems, with ecological and evolutionary legacies still evident in modern seas. Current anthropogenic global changes increase extinction risk and pose a significant threat to marine ecosystems, which are critical for human use and sustenance. The evaluation of these threats and the likely responses of marine ecosystems requires a better understanding of evolutionary processes that affect marine ecosystems under global change. Here, we discuss how knowledge of ( a) changes in biodiversity of ancient marine ecosystems to past extinctions events, ( b) the patterns of sensitivity and biodiversity loss in modern marine taxa, and ( c) the physiological mechanisms underpinning species’ sensitivity to global change can be exploited and integrated to advance our critical thinking in this area.

Surface and Subsurface Quality Evaluation of Engineered Wood Products by Ultrasonic Means

2014 ◽  
pp. 182-220
Author(s):  
Frank C. Beall ◽  
Henrique Reis
Keyword(s):  
Product Development ◽  
Material Properties ◽  
Rapid Evolution ◽  
Solid Wood ◽  
Wood Products ◽  
Assessment And Evaluation ◽  
Engineered Wood Products ◽  
Engineered Wood ◽  
History Of ◽  
Ultrasonic Techniques

The use of ultrasonic techniques to evaluate the properties of engineered wood-based materials is discussed with respect to research to date and the use of more advanced techniques. The latter is critical because of the rapid evolution from solid wood to reconstituted structural materials. In addition, although considerable research has been done, there have been few introductions into manufacturing. This chapter traces the history of the use and latest developments of ultrasonics in several key areas, particularly the measurement of adhesive curing and quality in composites and laminates, and detection of flaws in solid wood materials. The techniques reviewed apply to product development, material properties, process control, product quality assessment, and evaluation of products in service.

Mass Extinctions and the Structure and Function of Ecosystems

2013 ◽  
Vol 19 ◽  
pp. 115-156 ◽  
Author(s):  
Pincelli M. Hull ◽  
Simon A. F. Darroch
Keyword(s):  
Biodiversity Loss ◽  
Structure And Function ◽  
Ecosystem Change ◽  
Mass Extinctions ◽  
General Introduction ◽  
Biodiversity Crisis ◽  
Ecosystem Effects ◽  
History Of ◽  
Research Questions ◽  
And Function

Mass extinctions shape the history of life and can be used to inform understanding of the current biodiversity crisis. In this paper, a general introduction is provided to the methods used to investigate the ecosystem effects of mass extinctions (Part I) and to explore major patterns and outstanding research questions in the field (Part II). The five largest mass extinctions of the Phanerozoic had profoundly different effects on the structure and function of ecosystems, although the causes of these differences are currently unclear. Outstanding questions and knowledge gaps are identified that need to be addressed if the fossil record is to be used as a means of informing the dynamics of future biodiversity loss and ecosystem change.

scholarly journals An integrative genomic analysis of the Longshanks selection experiment for longer limbs in mice

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
João PL Castro ◽  
Michelle N Yancoskie ◽  
Marta Marchini ◽  
Stefanie Belohlavy ◽  
Layla Hiramatsu ◽  
...  
Keyword(s):  
Bone Growth ◽  
Rapid Evolution ◽  
Genomic Analysis ◽  
Selection Response ◽  
Major Effect ◽  
Selection Experiment ◽  
Genomic Analyses ◽  
Selection Experiments ◽  
Polygenic Adaptation ◽  
History Of

Evolutionary studies are often limited by missing data that are critical to understanding the history of selection. Selection experiments, which reproduce rapid evolution under controlled conditions, are excellent tools to study how genomes evolve under selection. Here we present a genomic dissection of the Longshanks selection experiment, in which mice were selectively bred over 20 generations for longer tibiae relative to body mass, resulting in 13% longer tibiae in two replicates. We synthesized evolutionary theory, genome sequences and molecular genetics to understand the selection response and found that it involved both polygenic adaptation and discrete loci of major effect, with the strongest loci tending to be selected in parallel between replicates. We show that selection may favor de-repression of bone growth through inactivating two limb enhancers of an inhibitor, Nkx3-2. Our integrative genomic analyses thus show that it is possible to connect individual base-pair changes to the overall selection response.

Relaxed Selection and the Rapid Evolution of Reproductive Genes

2020 ◽  
Vol 36 (9) ◽  
pp. 640-649 ◽  
Author(s):  
Amy L. Dapper ◽  
Michael J. Wade
Keyword(s):  
Rapid Evolution ◽  
Relaxed Selection ◽  
Reproductive Genes

The Triassic U–Pb age for the aquatic long-necked protorosaur of Guizhou, China

2014 ◽  
Vol 151 (4) ◽  
pp. 749-754 ◽  
Author(s):  
YANBIN WANG ◽  
DETING YANG ◽  
JUAN HAN ◽  
LITING WANG ◽  
JIANXIN YAO ◽  
...  
Keyword(s):  
Middle Triassic ◽  
Rapid Evolution ◽  
Guizhou Province ◽  
Ion Microprobe ◽  
Isotopic Age ◽  
Zircon Age ◽  
Marine Reptiles ◽  
Wide Range ◽  
History Of ◽  
Permian Mass Extinction

AbstractThe ancient marine limestone beds of the upper part of the Guanling Formation, Panxian County, Guizhou Province, SW China, yielded a wide range of high-diversity well-preserved marine reptiles such as the fully aquatic protorosaur with an extremely long neckDinocephalosaurus orientalis, the oldest mixosaurid ichthyosaurs and lariosaurs. However, there is no precise isotopic age to study the intriguing origin, evolution and emigration history of the important fauna. We report a sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon age for a volcanic tuff bed within the upper part of the Guanling Formation. The result indicates that the age of the fossil horizon is 244.0±1.3 Ma, 14 Ma earlier than the previously estimated age based on conodont evidence. We consider that the marine reptiles had a relatively rapid evolution during Middle Triassic time, some 8 Ma after the end-Permian mass extinction.

scholarly journals 7000 years of turnover: historical contingency and human niche construction shape the Caribbean's Anthropocene biota

2020 ◽  
Vol 287 (1927) ◽  
pp. 20200447 ◽  
Author(s):  
Melissa E. Kemp ◽  
Alexis M. Mychajliw ◽  
Jenna Wadman ◽  
Amy Goldberg
Keyword(s):  
Cultural Practices ◽  
Biodiversity Loss ◽  
Modern Human ◽  
Priority Effects ◽  
Modern World ◽  
Historical Contingency ◽  
Spatial And Temporal Patterns ◽  
Species Introductions ◽  
History Of ◽  
The Caribbean

The human-mediated movement of species across biogeographic boundaries—whether intentional or accidental—is dramatically reshaping the modern world. Yet humans have been reshaping ecosystems and translocating species for millennia, and acknowledging the deeper roots of these phenomena is important for contextualizing present-day biodiversity loss, ecosystem functioning and management needs. Here, we present the first database of terrestrial vertebrate species introductions spanning the entire anthropogenic history of a system: the Caribbean. We employ this approximately 7000-year dataset to assess the roles of historical contingency and priority effects in shaping present-day community structure and conservation outcomes, finding that serial human colonization events contributed to habitat modifications and species extinctions that shaped the trajectories of subsequent species introductions by other human groups. We contextualized spatial and temporal patterns of species introductions within cultural practices and population histories of Indigenous, colonial and modern human societies, and show that the taxonomic and biogeographic diversity of introduced species reflects diversifying reasons for species introductions through time. Recognition of the complex social and economic structures across the 7000-year human history of the Caribbean provides the necessary context for interpreting the formation of an Anthropocene biota.

scholarly journals Zoantharia (Cnidaria: Hexacorallia) of the Dutch Caribbean and One New Species of Parazoanthus

Diversity ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 190
Author(s):  
Javier Montenegro ◽  
Bert W. Hoeksema ◽  
Maria E. A. Santos ◽  
Hiroki Kise ◽  
James Davis Reimer
Keyword(s):  
Coral Reefs ◽  
Biodiversity Loss ◽  
Anthropogenic Pressure ◽  
Undescribed Species ◽  
Species List ◽  
History Of Research ◽  
History Of ◽  
The Caribbean ◽  
Dutch Caribbean ◽  
One New Species

Species of the anthozoan order Zoantharia (=Zoanthidea) are common components of subtropical and tropical shallow water coral reefs. Despite a long history of research on their species diversity in the Caribbean, many regions within this sea remain underexamined. One such region is the Dutch Caribbean, including the islands of St. Eustatius, St. Maarten, Saba, Aruba, Bonaire, and Curaçao, as well as the Saba Bank, for which no definitive species list exists. Here, combining examinations of specimens housed in the Naturalis Biodiversity Center collection with new specimens and records from field expeditions, we provide a list of zoantharian species found within the Dutch Caribbean. Our results demonstrate the presence at least 16 described species, including the newly described Parazoanthus atlanticus, and the additional potential presence of up to four undescribed species. These records of new and undescribed species demonstrate that although the zoantharian research history of the Caribbean is long, further discoveries remain to be found. In light of biodiversity loss and increasing anthropogenic pressure on declining coral reefs, documenting the diversity of zoantharians and other coral reef species to provide baseline data takes on a new urgency.

scholarly journals Holocene history of fire, vegetation and land use from the central Pyrenees (France)

2012 ◽  
Vol 77 (1) ◽  
pp. 54-64 ◽  
Author(s):  
Damien Rius ◽  
Boris Vanniére ◽  
Didier Galop
Keyword(s):  
Land Use ◽  
Late Holocene ◽  
Landscape Management ◽  
Fire Regimes ◽  
Fire Frequency ◽  
Subsequent Reduction ◽  
Human Land Use ◽  
History Of ◽  
In Fire ◽  
Central Pyrenees

Located on a mountain pass in the west-central Pyrenees, the Col d'Ech peat bog provides a Holocene fire and vegetation record based upon nine 14C (AMS) dates. We aim to compare climate-driven versus human-driven fire regimes in terms of frequency, fire episodes distribution, and impact on vegetation. Our results show the mid-Holocene (8500–5500 cal yr BP) to be characterized by high fire frequency linked with drier and warmer conditions. However, fire occurrences appear to have been rather stochastic as underlined by a scattered chronological distribution. Wetter and colder conditions at the mid-to-late Holocene transition (4000–3000 cal yr BP) led to a decrease in fire frequency, probably driven by both climate and a subsequent reduction in human land use. On the contrary, from 3000 cal yr BP, fire frequency seems to be driven by agro-pastoral activities with a very regular distribution of events. During this period fire was used as a prominent agent of landscape management.

Syntactic variation in the history of Norwegian and the decline of XV word order

Diachronica ◽  
2006 ◽  
Vol 23 (1) ◽  
pp. 105-141 ◽  
Author(s):  
John D. Sundquist
Keyword(s):  
Word Order ◽  
Information Structure ◽  
Language Contact ◽  
Underlying Structure ◽  
Syntactic Variation ◽  
15Th Century ◽  
Case Morphology ◽  
History Of ◽  
Exogenous Factors ◽  
Subsequent Loss

This essay examines syntactic variation between Complement–Verb (XV) and Verb–Complement (VX) order in a corpus of Middle Norwegian texts written between 1250 and 1525. In comparison to traditional studies which relate word order variation and the subsequent loss of XV word order to overt case morphology, this analysis proposes that information structure and variation in the underlying structure of the VP play a significant role. Empirical data point to the interaction of endogenous and exogenous factors, including language contact between Norwegian and Danish, which ultimately brings about the decline of XV word order in 15th-century Norwegian.

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