Chapter 24 first described how scientists study events in the history of life, and then presented several types of evidence for the changes that have occurred on Earth over millions of years. The following links allow you to investigate many of these topics further.
24.1 Tools for Studying History
Follow a Fossil
The fossil record is one of the most important tools for tracking the changes in species throughout the geologic record. This site from the Denver Museum of Natural History describes some of the basics of finding, collecting, preserving, and analyzing fossils.
Keywords: fossil record, excavation, evolution
Phylogeny of Life
The phylogeny wing of the UC-Berkeley Museum of Paleontology has a wealth of information about the evolution of organisms and the fossil evidence that scientists have used to support their evolutionary arguments. Follow the links through the different groups, and see how different fossils are used to construct phylogenetic trees.
Keywords: fossil record, evolution, phylogeny
This site provides a centralized location to find out what articles are being published and what current research is being done in the field of evolution. Many of the important journals and research institutes are listed and linked to.
Keywords: evolutionary research, paleontology, genetics
Burgess Shale Fossils
24.2 The Cambrian Explosion
The soft-bodied fossils of the Burgess Shale provided paleontologists and evolutionary biologists with a gold mine for studying changes in species. This site describes the fossils found in the shale deposits, and it also contains many links to other sites of interest concerning the Burgess Shale.
Keywords: Burgess Shale, fossil record, geologic time scale.
Searching for the First Animal
The Doushantuo deposits from southern China contained astonishing fossils of early animal embryos, providing paleontologists with yet another unique source of information about changes in the development and morphologies of species. This article describes how these fossils have sparked an entirely new way of looking at evolution using the fossil record.
Keywords: Cambrian, fossil embryo, Doushantuo
This Website describes the Ediacaran fossil deposits found in Southern Australia. Like the Burgess Shale and the Doushantuo deposits, the soft-bodied fossils found at this site provided paleontologists with a wealth of information about organisms of the Precambrian era.
Keywords: fossil, Ediacara, early animals
24.3 The Genetic Mechanism of Change
The "Molecular Evolution" link on the Evolution Homepage contains sites describing the unique questions and problems that molecular evolutionary biologists pose and face. The other links on the homepage lead to many other sites dealing with the topics covered in this chapter.
Keywords: fossil record, molecular evolution
Phylogeny of Darwin's Finches
24.4 Adaptive Radiations
Adaptive radiation is one potential source of rapid evolutionary change, often closely tied to studies in island biogeography. This article from the Proceedings of the National Academy of Science discusses how mtDNA has been used to infer the evolutionary history of Darwin's finches on the Galapagos Islands. This is a PDF document. You will need the Adobe Reader plugin for your browser.
Keywords: adaptive radiation, variation, biodiversity, island biogeography, mtDNA, phylogeny
The KT Extinction
24.5 Mass Extinctions
This essay by Richard Cowen of UC-Davis discusses the wealth of evidence that supports the asteroid hypothesis for the Cretaceous-Tertiary extinction. Cowen discusses the impact that an asteroid collision may have had on many physiological and evolutionary processes.
Keywords: KT extinction, mass extinction, asteroid hypothesis
The Sixth Extinction
This page discusses recent theories voiced by many biologists claiming that the biosphere is currently undergoing a sixth episode of mass extinction, possibly due to human influence. Many links at the bottom of the page lead to various research institutes and articles supporting both sides of the theory.
Keywords: mass extinction, biodiversity, conservation