Oncology & Cancer

When does a cancer first arise?

There is no stronger risk factor for cancer than age. At the time of diagnosis, the median age of patients across all cancers is 66. That moment, however, is the culmination of years of clandestine tumor growth, and the answer ...

Medical research

Measles origin finding could inform COVID-19 research

An international group of researchers has tackled the controversial question of when measles first emerged, finding it could be linked to the rise of large cities. The team sequenced the genome of a measles strain from 1912 ...

Diseases, Conditions, Syndromes

Coronavirus was already spreading in U.S. in January: study

(HealthDay)—More evidence has surfaced that the COVID-19 coronavirus was circulating in the United States as much as a month prior to the first confirmed local case in February, the U.S. Centers for Disease Control and ...

Diseases, Conditions, Syndromes

Sequencing the MERS coronavirus outbreak in Saudi Arabia

(Medical Xpress)—Using deep sequencing technologies, researchers from the Kingdom of Saudi Arabia, US, Canada and the UK have shown that the novel Middle East Respiratory Syndrome (MERS) coronavirus can spread between people ...

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Common descent

A group of organisms is said to have common descent if they have a common ancestor. In modern biology, it is generally accepted that all living organisms on Earth are descended from a common ancestor or ancestral gene pool.

A theory of universal common descent via an evolutionary process was proposed by Charles Darwin in his book On the Origin of Species (1859), and later in The Descent of Man (1871). This theory is now generally accepted by biologists, and the last universal common ancestor (LUCA or LUA), that is, the most recent common ancestor of all currently living organisms, is believed to have appeared about 3.9 billion years ago. The theory of a common ancestor between all organisms is one of the principles of evolution, although for single cell organisms and viruses, single phylogeny is disputed (see: origin of life).

In his book The Ancestor's Tale, Richard Dawkins uses the word concestor as a substitute for "common ancestor." This new word is very gradually entering scientific parlance.

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