Aug 2023
The hardy genus Takakia has survived 400 million years but is losing ground in the Himalayas
The fastest-evolving moss in the world may not adapt to climate change
Jan 2015
Conifers are predominantly cone-bearing, evergreen trees and shrubs belonging to the order Pinales, as well as a small number of extinct orders, in the class Pinopsida of the division Pinophyta (Coniferophyta). All are woody plants, and they are often the predominant trees of forests worldwide, including pine, spruce, fir, hemlock, cedar, larch, juniper, cypress, yew, and redwood species. Because the ovules (young seeds) of these plants are exposed directly to the air at the time of pollination—that is, these plants produce seeds that are not enclosed in a fruit or ovary—conifers are classified as gymnosperms. (In contrast, the flowering plants, or angiosperms, have ovules enclosed in an ovary.) Today, conifers constitute the principal source of lumber and pulp for paper and wood products. See also: Forest and forestry; Forest timber resources; Lumber; Pinales; Pinophyta; Pinopsida; Tree; Wood products
Conifers
Mar 2020
Life on Earth has been punctuated by a number of catastrophic mass extinctions throughout history. During these events, diverse taxonomic groups collapsed from the relatively rapid and widespread extinction of large numbers of species. Precipitated by a massive asteroid impact on Earth that occurred more than 65 million years ago, the end-Cretaceous mass extinction led to the obliteration of forests around the world and caused the disappearance of approximately three-fourths of all plant and animal life on Earth. Most notably, all nonavian dinosaurs went extinct at that time. Included in that extinction event were many species of prehistoric birds (avians), which are considered by taxonomists to be members of the dinosaur family. Larger avian species that were dependent on trees for nesting or food comprised the majority of extinctions. However, smaller ancestral forms of ground-dwelling birds survived. See also: Aves; Chicxulub impact crater; Cretaceous; Dinosauria; Extinction; Extinction (paleontology); Forest; Mass extinctions; Tree
Ground-dwelling birds survived the end-Cretaceous mass extinction