Temporally varying disruptive selection in the medium ground finch (
            Geospiza fortis
            )

Disruptive natural selection within populations exploiting different resources is considered to be a major driver of adaptive radiation and the production of biodiversity. Fitness functions, which describe the relationships between trait variation and fitness, can help to illuminate how this disruptive selection leads to population differentiation. However, a single fitness function represents only a particular selection regime over a single specified time period (often a single season or a year), and therefore might not capture longer-term dynamics. Here, we build a series of annual fitness functions that quantify the relationships between phenotype and apparent survival. These functions are based on a 9-year mark–recapture dataset of over 600 medium ground finches ( Geospiza fortis ) within a population bimodal for beak size. We then relate changes in the shape of these functions to climate variables. We find that disruptive selection between small and large beak morphotypes, as reported previously for 2 years, is present throughout the study period, but that the intensity of this selection varies in association with the harshness of environment. In particular, we find that disruptive selection was strongest when precipitation was high during the dry season of the previous year. Our results shed light on climatic factors associated with disruptive selection in Darwin's finches, and highlight the role of temporally varying fitness functions in modulating the extent of population differentiation.

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Acoustic discrimination of sympatric morphs in Darwin's finches: a behavioural mechanism for assortative mating?

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2009.0289 ◽

2010 ◽

Vol 365 (1543) ◽

pp. 1031-1039 ◽

Cited By ~ 40

Author(s):

Jeffrey Podos

Keyword(s):

Assortative Mating ◽

Disruptive Selection ◽

Evolutionary Divergence ◽

Santa Cruz Island ◽

Evolutionary Diversification ◽

Acoustic Discrimination ◽

Behavioural Types ◽

Geospiza Fortis ◽

Beak Size ◽

Behavioural Mechanism

Populations with multiple morphological or behavioural types provide unique opportunities for studying the causes and consequences of evolutionary diversification. A population of the medium ground finch ( Geospiza fortis ) at El Garrapatero on Santa Cruz Island, Galápagos, features two beak size morphs. These morphs produce acoustically distinctive songs, are subject to disruptive selection and mate assortatively by morph. The main goal of the present study was to assess whether finches from this population are able to use song as a cue for morph discrimination. A secondary goal of this study was to evaluate whether birds from this population discriminate songs of their own locality versus another St Cruz locality, Borrero Bay, approximately 24 km to the NW. I presented territorial males with playback of songs of their own morph, of the other morph, and of males from Borrero Bay. Males responded more strongly to same-morph than to other-morph playbacks, showing significantly shorter latencies to flight, higher flight rates and closer approaches to the playback speaker. By contrast, I found only minor effects of locality on responsiveness. Evidence for morph discrimination via acoustic cues supports the hypothesis that song can serve as a behavioural mechanism for assortative mating and sympatric evolutionary divergence.

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Disruptive selection in a bimodal population of Darwin's finches

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2008.1321 ◽

2008 ◽

Vol 276 (1657) ◽

pp. 753-759 ◽

Cited By ~ 75

Author(s):

Andrew P Hendry ◽

Sarah K Huber ◽

Luis F De León ◽

Anthony Herrel ◽

Jeffrey Podos

Keyword(s):

Adaptive Radiation ◽

Spatial And Temporal Variation ◽

Disruptive Selection ◽

Adaptive Divergence ◽

Santa Cruz Island ◽

Santa Cruz ◽

Prolonged Drought ◽

Geospiza Fortis ◽

Beak Size ◽

Insight Into

A key part of the ecological theory of adaptive radiation is disruptive selection during periods of sympatry. Some insight into this process might be gained by studying populations that are bimodal for dual-context traits, i.e. those showing adaptive divergence and also contributing to reproductive isolation. A population meeting these criteria is the medium ground finch ( Geospiza fortis ) of El Garrapatero, Santa Cruz Island, Galápagos. We examined patterns of selection in this population by relating individual beak sizes to interannual recaptures during a prolonged drought. Supporting the theory, disruptive selection was strong between the two beak size modes. We also found some evidence of selection against individuals with the largest and smallest beak sizes, perhaps owing to competition with other species or to gaps in the underlying resource distribution. Selection may thus simultaneously maintain the current bimodality while also constraining further divergence. Spatial and temporal variation in G. fortis bimodality suggests a dynamic tug of war among factors such as selection and assortative mating, which may alternatively promote or constrain divergence during adaptive radiation.

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A meta-analysis of the literature on climate change and migration

Journal of Demographic Economics ◽

10.1017/dem.2019.22 ◽

2021 ◽

pp. 1-52

Author(s):

Michel Beine ◽

Lionel Jeusette

Keyword(s):

Climate Change ◽

Climatic Factors ◽

Human Mobility ◽

Meta Analysis ◽

Empirical Studies ◽

Displacement Effect ◽

Methodological Choices ◽

Econometric Methods ◽

And Migration

Abstract Recent surveys of the literature on climate change and migration emphasize the important diversity of outcomes and approaches of the empirical studies. In this paper, we conduct a meta-analysis in order to investigate the role of the methodological choices of these empirical studies in finding some particular results concerning the role of climatic factors as drivers of human mobility. We code 51 papers representative of the literature in terms of methodological approaches. This results in the coding of more than 85 variables capturing the methodology of the main dimensions of the analysis at the regression level. These dimensions include authors' reputation, type of mobility, measures of mobility, type of data, context of the study, econometric methods, and last but not least measures of the climatic factors. We look at the influence of these characteristics on the probability of finding any effect of climate change, a displacement effect, an increase in immobility, and evidence in favor of a direct vs. an indirect effect. Our results highlight the role of some important methodological choices, such as the frequency of the data on mobility, the level of development, the measures of human mobility and of the climatic factors as well as the econometric methodology.

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Possible Role of High-Dose Barbiturates and Early Administration of Parenteral Ketogenic Diet for Reducing Development of Chronic Epilepsy in Febrile Infection-Related Epilepsy Syndrome: A Case Report

Neuropediatrics ◽

10.1055/s-0040-1716903 ◽

2020 ◽

Author(s):

Shimpei Baba ◽

Tohru Okanishi ◽

Koichi Ohsugi ◽

Rika Suzumura ◽

Keiko Niimi ◽

...

Keyword(s):

Continuous Infusion ◽

Ketogenic Diet ◽

Epilepsy Syndrome ◽

High Dose ◽

Early Administration ◽

Chronic Epilepsy ◽

Time Period ◽

Irreversible Brain Damage ◽

Electroencephalogram Eeg

AbstractWe describe the efficacy of high-dose barbiturates and early administration of a parenteral ketogenic diet (KD) as initial treatments for acute status epilepticus (SE) in an 8-year-old girl with febrile infection-related epilepsy syndrome (FIRES). The patient was admitted to our hospital with refractory focal SE. Abundant epileptic discharges over the left frontal region were observed on electroencephalogram (EEG). Treatment with continuous infusion of thiamylal for 4 hours, increased incrementally to 40 mg/kg/h, successfully ended the clinical SE, and induced a burst-suppression coma. The infusion rate was then gradually decreased to 4 mg/kg/h over the next 12 hours. Parenteral KD was administered from days 6 to 21 of illness. Continuous infusion of thiamylal was switched to midazolam on day 10 without causing seizures or EEG exacerbations. The patient has remained seizure free in the 15 months since hospital discharge. The effectiveness of KD for the treatment of FIRES has attracted attention amongst clinicians, but KD treatment may need to last for 2 to 4 days before it can stop SE, a time period that could cause irreversible brain damage. Considering the severity of SE in our patient and the dose of barbiturates needed to treat it, we consider this case to have had a good clinical outcome. The results suggest that rapid termination of seizure using high-dose barbiturates in conjunction with early administration of parenteral KD could reduce the development of chronic epilepsy in patients with FIRES.

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The role of environmental conditions, climatic factors and spatial processes in driving multiple facets of stream macroinvertebrate beta diversity in a climatically heterogeneous mountain region

Ecological Indicators ◽

10.1016/j.ecolind.2021.107407 ◽

2021 ◽

Vol 124 ◽

pp. 107407

Author(s):

Xiaoming Jiang ◽

Baozhu Pan ◽

Wanxiang Jiang ◽

Yiming Hou ◽

Haiqiang Yang ◽

...

Keyword(s):

Environmental Conditions ◽

Beta Diversity ◽

Climatic Factors ◽

Mountain Region ◽

Spatial Processes ◽

Stream Macroinvertebrate

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Beyond Interactive Evolution: Expressing Intentions Through Fitness Functions

Leonardo ◽

10.1162/leon_a_01103 ◽

2016 ◽

Vol 49 (3) ◽

pp. 251-256 ◽

Cited By ~ 1

Author(s):

Penousal Machado ◽

Tiago Martins ◽

Hugo Amaro ◽

Pedro H. Abreu

Keyword(s):

Fitness Function ◽

Interactive Art ◽

Support Tool ◽

Generative Art ◽

Fitness Functions ◽

Meta Level ◽

Evolutionary Art ◽

Creativity Support ◽

The Creation ◽

The Impact

Photogrowth is a creativity support tool for the creation of nonphotorealistic renderings of images. The authors discuss its evolution from a generative art application to an interactive evolutionary art tool and finally into a meta-level interactive art system in which users express their artistic intentions through the design of a fitness function. The authors explore the impact of these changes on the sense of authorship, highlighting the range of imagery that can be produced by the system.

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Identification and developmental regulation of a neuron-specific subunit of cytoplasmic dynein.

Molecular Biology of the Cell ◽

10.1091/mbc.7.2.331 ◽

1996 ◽

Vol 7 (2) ◽

pp. 331-343 ◽

Cited By ~ 45

Author(s):

K K Pfister ◽

M W Salata ◽

J F Dillman ◽

E Torre ◽

R J Lye

Keyword(s):

Axonal Transport ◽

Developmental Regulation ◽

Cytoplasmic Dynein ◽

Retrograde Axonal Transport ◽

Protein Isoforms ◽

Cultured Neurons ◽

Developmentally Regulated ◽

Time Period ◽

Intermediate Chains

Cytoplasmic dynein is the microtubule minus-end-directed motor for the retrograde axonal transport of membranous organelles. Because of its similarity to the intermediate chains of flagellar dynein, the 74-kDa intermediate chain (IC74) subunit of dynein is thought to be involved in binding dynein to its membranous organelle cargo. Previously, we identified six isoforms of the IC74 cytoplasmic dynein subunit in the brain. We further demonstrated that cultured glia and neurons expressed different dynein IC74 isoforms and phospho-isoforms. Two isoforms were observed when dynein from glia was analyzed. When dynein from cultured neurons was analyzed, six IC74 isoforms were observed, although the relative amounts of the dynein isoforms from cultured neurons differed from those found in dynein from brain. To better understand the role of the neuronal IC74 isoforms and identify neuron-specific IC74 dynein subunits, the expression of the IC74 protein isoforms and mRNAs of various tissues were compared. As a result of this comparison, the identity of each of the isoform spots observed on two-dimensional gels was correlated with the products of each of the IC74 mRNAs. We also found that between the fifteenth day of gestation (E15) and the fifth day after birth (P5), the relative expression of the IC74 protein isoforms changes, demonstrating that the expression of IC74 isoforms is developmentally regulated in brain. During this time period, there is relatively little change in the abundance of the various IC74 mRNAs. The E15 to P5 time period is one of rapid process extension and initial pattern formation in the rat brain. This result indicates that the changes in neuronal IC74 isoforms coincide with neuronal differentiation, in particular the extension of processes. This suggests a role for the neuronal IC74 isoforms in the establishment or regulation of retrograde axonal transport.

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Patterns of population differentiation in annual killifishes from the Paraná-Uruguay-La Plata Basin: the role of vicariance and dispersal

Journal of Biogeography ◽

10.1111/j.1365-2699.2012.02722.x ◽

2012 ◽

Vol 39 (9) ◽

pp. 1707-1719 ◽

Cited By ~ 23

Author(s):

Graciela García ◽

Verónica Gutiérrez ◽

Julia Vergara ◽

Pablo Calviño ◽

Alejandro Duarte ◽

...

Keyword(s):

Population Differentiation ◽

La Plata ◽

La Plata Basin

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Exodus

After Dinner Conversation ◽

10.5840/adc2021211102 ◽

2021 ◽

Vol 2 (11) ◽

pp. 37-51

Author(s):

Geoffrey Hart ◽

Keyword(s):

Short Story ◽

Jewish People ◽

Deep Space ◽

Traditional Foods ◽

Religious Ceremony ◽

Time Period ◽

Archeological Evidence ◽

Historical Basis ◽

The Right

What makes a "religious" holiday? Does the combination of ritual, culture, and family custom all merge together to create "religion?" Does it even matter if the historical basis for religious stories are false? In this work of philosophical short story fiction, the spaceship computer AI wakes up a family in deep space hibernation to give them time to prepare for, and celebrate, Passover. There are many situations unique to being in space that must be overcome; determining the right time period when taking into consideration time dilation, not to mention missing ingredients for traditional foods. Also, they are short two people of the requisite ten and ask the computer AI to "convert" and serve the role of two additional Jewish people. Awkwardly, the computer reminds them that some of their traditional stories are not supported by archeological evidence. This all begs important questions about the complicated weaving of history, faith, culture, and family custom in religious ceremony.

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