Climate change during the deposition of the Aptian Santana Formation (Araripe Basin, Brazil): Preliminary data based on wood signatures

Author(s):  
Margot Guerra-Sommer ◽  
Anelise Marta Siegloch ◽  
Isabela Degani-Schmidt ◽  
Ângela Cristine Scaramuzza dos Santos ◽  
Ismar de Souza Carvalho ◽  
...  
2019 ◽  
Vol 3 (6) ◽  
pp. 723-729
Author(s):  
Roslyn Gleadow ◽  
Jim Hanan ◽  
Alan Dorin

Food security and the sustainability of native ecosystems depends on plant-insect interactions in countless ways. Recently reported rapid and immense declines in insect numbers due to climate change, the use of pesticides and herbicides, the introduction of agricultural monocultures, and the destruction of insect native habitat, are all potential contributors to this grave situation. Some researchers are working towards a future where natural insect pollinators might be replaced with free-flying robotic bees, an ecologically problematic proposal. We argue instead that creating environments that are friendly to bees and exploring the use of other species for pollination and bio-control, particularly in non-European countries, are more ecologically sound approaches. The computer simulation of insect-plant interactions is a far more measured application of technology that may assist in managing, or averting, ‘Insect Armageddon' from both practical and ethical viewpoints.


2019 ◽  
Vol 3 (2) ◽  
pp. 221-231 ◽  
Author(s):  
Rebecca Millington ◽  
Peter M. Cox ◽  
Jonathan R. Moore ◽  
Gabriel Yvon-Durocher

Abstract We are in a period of relatively rapid climate change. This poses challenges for individual species and threatens the ecosystem services that humanity relies upon. Temperature is a key stressor. In a warming climate, individual organisms may be able to shift their thermal optima through phenotypic plasticity. However, such plasticity is unlikely to be sufficient over the coming centuries. Resilience to warming will also depend on how fast the distribution of traits that define a species can adapt through other methods, in particular through redistribution of the abundance of variants within the population and through genetic evolution. In this paper, we use a simple theoretical ‘trait diffusion’ model to explore how the resilience of a given species to climate change depends on the initial trait diversity (biodiversity), the trait diffusion rate (mutation rate), and the lifetime of the organism. We estimate theoretical dangerous rates of continuous global warming that would exceed the ability of a species to adapt through trait diffusion, and therefore lead to a collapse in the overall productivity of the species. As the rate of adaptation through intraspecies competition and genetic evolution decreases with species lifetime, we find critical rates of change that also depend fundamentally on lifetime. Dangerous rates of warming vary from 1°C per lifetime (at low trait diffusion rate) to 8°C per lifetime (at high trait diffusion rate). We conclude that rapid climate change is liable to favour short-lived organisms (e.g. microbes) rather than longer-lived organisms (e.g. trees).


2020 ◽  
Vol 5 (1) ◽  
pp. 131-141
Author(s):  
Cristina Rincon ◽  
Kia Noelle Johnson ◽  
Courtney Byrd

Purpose The purpose of this study is to examine the frequency and type of speech disfluencies (stuttering-like and nonstuttering-like) in bilingual Spanish–English (SE) children who stutter (CWS) to SE children who do not stutter (CWNS) during narrative samples elicited in Spanish and English to provide further diagnostic information for this population and preliminary data toward an expansion of this study. Method Participants included six bilingual SE children (three CWS, three CWNS) ranging in age from 5 years to 7;5 (years;months) and recruited from the surrounding Houston, Texas area. Participants provided a narrative sample in English and Spanish. The frequency of speech disfluencies was tabulated, and mean length of utterance was measured for each sample. Results Results indicate that both talker groups exceed the diagnostic criteria typically used for developmental stuttering. Regardless of the language being spoken, CWS participants had a frequency of stuttering-like speech disfluencies that met or exceeded the diagnostic criteria for developmental stuttering that is based on monolingual English speakers. The CWNS participants varied in meeting the criteria depending on the language being spoken, with one of the three CWNS exceeding the criteria in both languages and one exceeding the criteria for percentage of stuttering-like speech disfluencies in one language. Conclusion Findings from this study contribute to the development of more appropriate diagnostic criteria for bilingual SE-speaking children to aid in the reduction of misdiagnoses of stuttering in this population.


2001 ◽  
Vol 70 (1) ◽  
pp. 47-61 ◽  
Author(s):  
Robert Moss ◽  
James Oswald ◽  
David Baines

2008 ◽  
Vol 7 ◽  
pp. 64-64
Author(s):  
J SPINAR ◽  
J VITOVEC ◽  
J KETTNER ◽  
A LINHART ◽  
L DUSEK ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document