Diseases, Conditions, Syndromes

XBB and BQ.1: what we know about these two omicron 'cousins'

In late October, the UK Health Security Agency assigned variant designations to two new omicron "grandchildren": BQ.1 and XBB. This means they will be monitored by health authorities, but are not at this stage regarded as ...

Psychology & Psychiatry

Fighting misconceptions through intentionally designed figures

Associate professor of psychology and human development, Laura Novick, and graduate student Jingyi Liu, have published a paper highlighting the importance of intentionally and thoughtfully designed figures to explain evolutionary ...

Diseases, Conditions, Syndromes

Targeted travel restrictions fail to halt spread of COVID-19

As countries start to scale down their SARS-CoV-2 surveillance efforts, the results of a new study highlight the importance of continuing robust surveillance in regions of early spread for providing timely information on ...

Diseases, Conditions, Syndromes

New phylogenetic tool can handle the SARS-CoV-2 data load

Researchers at UC San Diego, in collaboration with UC Santa Cruz, have developed a new software tool for tracing and mapping the evolution of the SARS-CoV-2 virus, that is capable of handling the unprecedented amount of genetic ...

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A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to 6 m; some authors set a minimum of 10 cm trunk diameter (30 cm girth). Woody plants that do not meet these definitions by having multiple stems and/or small size, are called shrubs. Compared with most other plants, trees are long-lived, some reaching several thousand years old and growing to up to 115 m (379 ft) high.

Trees are an important component of the natural landscape because of their prevention of erosion and the provision of a weather-sheltered ecosystem in and under their foliage. Trees also play an important role in producing oxygen and reducing carbon dioxide in the atmosphere, as well as moderating ground temperatures. They are also elements in landscaping and agriculture, both for their aesthetic appeal and their orchard crops (such as apples). Wood from trees is a building material, as well as a primary energy source in many developing countries. Trees also play a role in many of the world's mythologies (see trees in mythology).

This text uses material from Wikipedia, licensed under CC BY-SA