منابع مشابه
Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines.
The population extinction pulse we describe here shows, from a quantitative viewpoint, that Earth's sixth mass extinction is more severe than perceived when looking exclusively at species extinctions. Therefore, humanity needs to address anthropogenic population extirpation and decimation immediately. That conclusion is based on analyses of the numbers and degrees of range contraction (indicati...
متن کاملAccelerated modern human–induced species losses: Entering the sixth mass extinction
The oft-repeated claim that Earth's biota is entering a sixth "mass extinction" depends on clearly demonstrating that current extinction rates are far above the "background" rates prevailing between the five previous mass extinctions. Earlier estimates of extinction rates have been criticized for using assumptions that might overestimate the severity of the extinction crisis. We assess, using e...
متن کاملColloquium paper: are we in the midst of the sixth mass extinction? A view from the world of amphibians.
Many scientists argue that we are either entering or in the midst of the sixth great mass extinction. Intense human pressure, both direct and indirect, is having profound effects on natural environments. The amphibians--frogs, salamanders, and caecilians--may be the only major group currently at risk globally. A detailed worldwide assessment and subsequent updates show that one-third or more of...
متن کاملAre we in the midst of the sixth mass extinction? A view from the world of amphibians
Many scientists argue that we are either entering or in the midst of the sixth great mass extinction. Intense human pressure, both direct and indirect, is having profound effects on natural environments. The amphibians—frogs, salamanders, and caecilians—may be the only major group currently at risk globally. A detailed worldwide assessment and subsequent updates show that onethird or more of th...
متن کاملThe Sixth Framework Programme
1. Project summary In this project we aim to invent and develop new techniques for the retrieval of figurative images (such as clip art, logos, signs) from large databases. Our techniques will be based on the extraction and matching of perceptually relevant shape features, thereby overcoming many of the limitations of existing methods. This project will develop and evaluate new algorithms for: ...
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ژورنال
عنوان ژورنال: Interdisciplinary Science Reviews
سال: 2000
ISSN: 0308-0188,1743-2790
DOI: 10.1179/030801800679260