George McGhee,
- Published in print:
- 2013
- Published Online:
- November 2015
- ISBN:
- 9780231160575
- eISBN:
- 9780231536363
- Item type:
- book
- Publisher:
- Columbia University Press
- DOI:
- 10.7312/columbia/9780231160575.001.0001
- Subject:
- Biology, Paleontology: Biology
The invasion of land by ocean-dwelling plants and animals was one of the most revolutionary events in the evolution of life on Earth, yet the animal invasion almost failed—twice—because of the twin ...
More
The invasion of land by ocean-dwelling plants and animals was one of the most revolutionary events in the evolution of life on Earth, yet the animal invasion almost failed—twice—because of the twin mass extinctions of the Late Devonian Epoch. Some 359 to 375 million years ago, these catastrophic events dealt our ancestors a blow that almost drove them back into the sea. If those extinctions had been just a bit more severe, spiders and insects—instead of vertebrates—might have become the ecologically dominant forms of animal life on land. This book examines the profound evolutionary consequences of the Late Devonian extinctions and the various theories proposed to explain their occurrence. Only one group of four-limbed vertebrates exists on Earth, while other tetrapod-like fishes are extinct. This gap is why the idea of “fish with feet” seems so peculiar to us, yet such animals were once a vital part of our world, and if the Devonian extinctions had not happened, members of these species, like the famous Acanthostega and Ichthyostega, might have continued to live in our rivers and lakes. Synthesizing research and a wealth of new discoveries, this book explores the causes of the Devonian extinctions, the reasons vertebrates were so severely affected, and the potential evolution of the modern world if the extinctions had never taken place.Less
The invasion of land by ocean-dwelling plants and animals was one of the most revolutionary events in the evolution of life on Earth, yet the animal invasion almost failed—twice—because of the twin mass extinctions of the Late Devonian Epoch. Some 359 to 375 million years ago, these catastrophic events dealt our ancestors a blow that almost drove them back into the sea. If those extinctions had been just a bit more severe, spiders and insects—instead of vertebrates—might have become the ecologically dominant forms of animal life on land. This book examines the profound evolutionary consequences of the Late Devonian extinctions and the various theories proposed to explain their occurrence. Only one group of four-limbed vertebrates exists on Earth, while other tetrapod-like fishes are extinct. This gap is why the idea of “fish with feet” seems so peculiar to us, yet such animals were once a vital part of our world, and if the Devonian extinctions had not happened, members of these species, like the famous Acanthostega and Ichthyostega, might have continued to live in our rivers and lakes. Synthesizing research and a wealth of new discoveries, this book explores the causes of the Devonian extinctions, the reasons vertebrates were so severely affected, and the potential evolution of the modern world if the extinctions had never taken place.
Alycia L. Stigall
- Published in print:
- 2016
- Published Online:
- May 2017
- ISBN:
- 9780226377445
- eISBN:
- 9780226377582
- Item type:
- chapter
- Publisher:
- University of Chicago Press
- DOI:
- 10.7208/chicago/9780226377582.003.0013
- Subject:
- Biology, Paleontology: Biology
Among modern taxa, speciation by geographic isolation is more prevalent than biologically‐based isolation mechanisms, and studies of speciation style among modern species indicate that vicariant ...
More
Among modern taxa, speciation by geographic isolation is more prevalent than biologically‐based isolation mechanisms, and studies of speciation style among modern species indicate that vicariant speciation has occurred much more frequently than speciation by dispersal in the development of the modern biota. Fewer analyses have tested the relative frequency of speciation styles in the fossil record directly, but these also found vicariance to be more widespread than dispersal speciation among Paleozoic marine benthos. The dramatic increase in human‐facilitated species invasions in recent decades has been documented to alter the evolutionary pathway of native species. Analyzing the evolutionary impacts of species invasions within the fossil record provides a framework for examining the impact of species introductions on evolutionary time scales. Both the Late Ordovician and Middle Devonian saw major invasions and suppression of speciation in benthic marine faunas. This seems to have occurred by depression of vicariance due to the ecological effects of invading species on native species.Less
Among modern taxa, speciation by geographic isolation is more prevalent than biologically‐based isolation mechanisms, and studies of speciation style among modern species indicate that vicariant speciation has occurred much more frequently than speciation by dispersal in the development of the modern biota. Fewer analyses have tested the relative frequency of speciation styles in the fossil record directly, but these also found vicariance to be more widespread than dispersal speciation among Paleozoic marine benthos. The dramatic increase in human‐facilitated species invasions in recent decades has been documented to alter the evolutionary pathway of native species. Analyzing the evolutionary impacts of species invasions within the fossil record provides a framework for examining the impact of species introductions on evolutionary time scales. Both the Late Ordovician and Middle Devonian saw major invasions and suppression of speciation in benthic marine faunas. This seems to have occurred by depression of vicariance due to the ecological effects of invading species on native species.
J. David Archibald and David E. Fastovsky
- Published in print:
- 2004
- Published Online:
- March 2012
- ISBN:
- 9780520242098
- eISBN:
- 9780520941434
- Item type:
- chapter
- Publisher:
- University of California Press
- DOI:
- 10.1525/california/9780520242098.003.0033
- Subject:
- Biology, Evolutionary Biology / Genetics
The disappearance of nonavian dinosaurs is only a small part of a greater class of extinctions known as “mass extinctions.” Mass extinctions are global events characterized by unusually high rates of ...
More
The disappearance of nonavian dinosaurs is only a small part of a greater class of extinctions known as “mass extinctions.” Mass extinctions are global events characterized by unusually high rates of extinction. The five episodes of mass extinctions in Earth history are the Permo-Triassic extinction, the Late Ordovician extinction, the Late Devonian extinction, the Triassic-Jurassic extinction, and the Cretaceous-Tertiary (K/T) extinction. This chapter focuses on patterns of geologic and biotic changes that occurred during the Cretaceous-Tertiary (K/T) extinction. It also highlights the similarities and differences in interpretations of geologic and fossil records. It concludes with two scenarios explaining the differing views about dinosaur extinction.Less
The disappearance of nonavian dinosaurs is only a small part of a greater class of extinctions known as “mass extinctions.” Mass extinctions are global events characterized by unusually high rates of extinction. The five episodes of mass extinctions in Earth history are the Permo-Triassic extinction, the Late Ordovician extinction, the Late Devonian extinction, the Triassic-Jurassic extinction, and the Cretaceous-Tertiary (K/T) extinction. This chapter focuses on patterns of geologic and biotic changes that occurred during the Cretaceous-Tertiary (K/T) extinction. It also highlights the similarities and differences in interpretations of geologic and fossil records. It concludes with two scenarios explaining the differing views about dinosaur extinction.
George R. McGhee
- Published in print:
- 2013
- Published Online:
- November 2015
- ISBN:
- 9780231160575
- eISBN:
- 9780231536363
- Item type:
- chapter
- Publisher:
- Columbia University Press
- DOI:
- 10.7312/columbia/9780231160575.003.0008
- Subject:
- Biology, Paleontology: Biology
This chapter discusses the impact of Devonian Extinction (End-Frasnian Catastrophe and End-Famennian Catastrophe) on the evolution of species. These catastrophes did not merely delay vertebrate ...
More
This chapter discusses the impact of Devonian Extinction (End-Frasnian Catastrophe and End-Famennian Catastrophe) on the evolution of species. These catastrophes did not merely delay vertebrate evolution; they also altered the direction of vertebrate evolution. Tetrapods suffered a sharp reduction in their previously morphologically diverse forms. In particular, the diversity of sizes seen in Frasnian tetrapods was lost, as only the mid-sized forms survived the catastrophe to repopulate during the Famennian period. Also, many of the peculiar tetrapod groups of the Early Carboniferous period had abandoned dry land entirely and returned to water after the Tournaisian Gap—a gap in the fossil records between End-Famennian Catastrophe and Carboniferous period.Less
This chapter discusses the impact of Devonian Extinction (End-Frasnian Catastrophe and End-Famennian Catastrophe) on the evolution of species. These catastrophes did not merely delay vertebrate evolution; they also altered the direction of vertebrate evolution. Tetrapods suffered a sharp reduction in their previously morphologically diverse forms. In particular, the diversity of sizes seen in Frasnian tetrapods was lost, as only the mid-sized forms survived the catastrophe to repopulate during the Famennian period. Also, many of the peculiar tetrapod groups of the Early Carboniferous period had abandoned dry land entirely and returned to water after the Tournaisian Gap—a gap in the fossil records between End-Famennian Catastrophe and Carboniferous period.
