Two Major Transitions in Earth History: Evidence for Two Lithospheric Strength Thresholds

2021 ◽  
Author(s):  
Kent Condie
Keyword(s):  
Major Transitions ◽  
Earth History

Homology, Genes, and Evolutionary Innovation

2014 ◽  
Author(s):  
Günter P. Wagner
Keyword(s):  
Evolutionary Biology ◽  
Regulatory Networks ◽  
Biological Diversity ◽  
Cell Types ◽  
Origin And Evolution ◽  
Major Transitions ◽  
Form And Function ◽  
Historical Continuity ◽  
Evolutionary Innovation ◽  
Character Identity

Homology—a similar trait shared by different species and derived from common ancestry, such as a seal's fin and a bird's wing—is one of the most fundamental yet challenging concepts in evolutionary biology. This book provides the first mechanistically based theory of what homology is and how it arises in evolution. The book argues that homology, or character identity, can be explained through the historical continuity of character identity networks—that is, the gene regulatory networks that enable differential gene expression. It shows how character identity is independent of the form and function of the character itself because the same network can activate different effector genes and thus control the development of different shapes, sizes, and qualities of the character. Demonstrating how this theoretical model can provide a foundation for understanding the evolutionary origin of novel characters, the book applies it to the origin and evolution of specific systems, such as cell types; skin, hair, and feathers; limbs and digits; and flowers. The first major synthesis of homology to be published in decades, this book reveals how a mechanistically based theory can serve as a unifying concept for any branch of science concerned with the structure and development of organisms, and how it can help explain major transitions in evolution and broad patterns of biological diversity.

LITTLE ICE AGE IN THE EARTH HISTORY AND ITS POSSIBLE REASONS

2020 ◽  
Vol 42 (1) ◽  
pp. 4-12
Author(s):  
Valeriy Fedorov ◽  
Denis Frolov
Keyword(s):  
Little Ice Age ◽  
Ice Age ◽  
Earth History ◽  
The Earth

Recent Earth History

1973 ◽  
Author(s):  
Claudio Vita-Finzi
Keyword(s):  
Earth History

The Major Transitions in Evolution

1997 ◽  
Author(s):  
John Maynard Smith ◽  
Eors Szathmary
Keyword(s):  
Full Range ◽  
Evolution Of Cooperation ◽  
Major Transitions ◽  
Insect Societies ◽  
Wide Range ◽  
Major Transition ◽  
Life Itself ◽  
History Of ◽  
Emergence Of Cooperation ◽  
Multicellular Organisms

Over the history of life there have been several major changes in the way genetic information is organized and transmitted from one generation to the next. These transitions include the origin of life itself, the first eukaryotic cells, reproduction by sexual means, the appearance of multicellular plants and animals, the emergence of cooperation and of animal societies, and the unique language ability of humans. This ambitious book provides the first unified discussion of the full range of these transitions. The authors highlight the similarities between different transitions--between the union of replicating molecules to form chromosomes and of cells to form multicellular organisms, for example--and show how understanding one transition sheds light on others. They trace a common theme throughout the history of evolution: after a major transition some entities lose the ability to replicate independently, becoming able to reproduce only as part of a larger whole. The authors investigate this pattern and why selection between entities at a lower level does not disrupt selection at more complex levels. Their explanation encompasses a compelling theory of the evolution of cooperation at all levels of complexity. Engagingly written and filled with numerous illustrations, this book can be read with enjoyment by anyone with an undergraduate training in biology. It is ideal for advanced discussion groups on evolution and includes accessible discussions of a wide range of topics, from molecular biology and linguistics to insect societies.

scholarly journals Oxygen and animals in Earth history

2014 ◽  
Vol 111 (11) ◽  
pp. 3907-3908 ◽  
Author(s):  
A. H. Knoll ◽  
E. A. Sperling
Keyword(s):  
Earth History

scholarly journals Chemical Stability of FeOOH at High Pressure and Temperature, and Oxygen Recycling in Early Earth History

2021 ◽  
Author(s):  
Egor Koemets ◽  
Timofey Fedotenko ◽  
Saiana Khandarkhaeva ◽  
Maxim Bykov ◽  
Elena Bykova ◽  
...  
Keyword(s):  
High Pressure ◽  
Chemical Stability ◽  
Early Earth ◽  
High Pressure And Temperature ◽  
Earth History

Chemical stability of FeOOH at high pressure and temperature, and oxygen recycling in early Earth history

2021 ◽  
Author(s):  
Egor Koemets ◽  
Timofey Fedotenko ◽  
Saiana Khandarkhaeva ◽  
Maxim Bykov ◽  
Elena Bykova ◽  
...  
Keyword(s):  
High Pressure ◽  
Chemical Stability ◽  
Early Earth ◽  
High Pressure And Temperature ◽  
Earth History

scholarly journals Olfactory coding in the antennal lobe of the bumble bee Bombus terrestris

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marcel Mertes ◽  
Julie Carcaud ◽  
Jean-Christophe Sandoz
Keyword(s):  
Honey Bees ◽  
Antennal Lobe ◽  
Bombus Terrestris ◽  
Bumble Bees ◽  
Foraging Strategies ◽  
Bumble Bee ◽  
Carbon Chain Length ◽  
Olfactory Coding ◽  
Major Transitions

AbstractSociality is classified as one of the major transitions in evolution, with the largest number of eusocial species found in the insect order Hymenoptera, including the Apini (honey bees) and the Bombini (bumble bees). Bumble bees and honey bees not only differ in their social organization and foraging strategies, but comparative analyses of their genomes demonstrated that bumble bees have a slightly less diverse family of olfactory receptors than honey bees, suggesting that their olfactory abilities have adapted to different social and/or ecological conditions. However, unfortunately, no precise comparison of olfactory coding has been performed so far between honey bees and bumble bees, and little is known about the rules underlying olfactory coding in the bumble bee brain. In this study, we used in vivo calcium imaging to study olfactory coding of a panel of floral odorants in the antennal lobe of the bumble bee Bombus terrestris. Our results show that odorants induce reproducible neuronal activity in the bumble bee antennal lobe. Each odorant evokes a different glomerular activity pattern revealing this molecule’s chemical structure, i.e. its carbon chain length and functional group. In addition, pairwise similarity among odor representations are conserved in bumble bees and honey bees. This study thus suggests that bumble bees, like honey bees, are equipped to respond to odorants according to their chemical features.

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