Tag Archives: Evolutionary Biology

Evolutionary biologist Lynn Margulis, a key figure in the development of the cellular endosymbiosis theory.
1966: The Evolutionary Theory of Endosymbiosis – Tracing the Origins of Cellular Complexity

Endosymbiosis, first proposed by Konstantin Mereschkowski and later advanced by Lynn Margulis, is a fundamental evolutionary theory explaining the origin of complex eukaryotic cells from symbiotic relationships with prokaryotic organisms

A 2009 photograph of Mount Graham, the tallest peak among the "sky islands" in southern Arizona, located near Tucson.
1943: Sky Islands – Unique Ecosystems of Isolated Mountain Peaks

Sky islands are isolated mountain ecosystems that showcase biodiversity changes due to geographic isolation, similar to oceanic islands

This image displays fossilized remains, encased in lithified seafloor sediments, of exoskeletons and other hard-shelled body parts from organisms that emerged around 550 million years ago. These fossils are indicative of the "Cambrian explosion," a period that saw a significant increase in life's diversity on Earth.
c. 550 Million BCE: Unraveling the Mysteries of the Cambrian Explosion

Explores the Cambrian Explosion, a pivotal period about 550 million years ago marked by a dramatic increase in life's diversity, including the emergence of hard-shelled eukaryotic organisms, and discusses the mass extinctions that followed

This image is an artist's concept showing aggregated collections of multicellular eukaryotes. Within the outer membrane, various types of cells are depicted, each designed to perform specific functions.
c. 1 Billion BCE: The Rise of Complex Multicellular Life

Explores the evolution of complex multicellular organisms, detailing their emergence about a billion years ago and highlighting key fossil evidence, such as the 650-million-year-old Doushantuo Formation. It also discusses the challenges faced by evolutionary biologists [...]

This image shows the fossilized remains of microfossils known as Eosphaera, located within the over 3.4-billion-year-old Gunflint chert formation in Pilbara, Western Australia. These microorganisms are thought to possibly represent transitional forms between prokaryotes and eukaryotes.
c. 2 Billion BCE: The Emergence of Eukaryotes – A Major Evolutionary Milestone

Discusses the evolutionary leap from prokaryotic to eukaryotic cells around 2 billion years ago, detailing the complex structures of eukaryotes and their significance in the diversification of life, including multicellular organisms like plants, fungi, and [...]