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  2. Faint young Sun paradox - Wikipedia

    en.wikipedia.org/wiki/Faint_young_Sun_paradox

    More recent modeling studies have shown that the Sun is currently 1.4 times as bright today than it was 4.6 billion years ago (Ga), and that the brightening has accelerated considerably. [8] At the surface of the Sun, more fusion power means a higher solar luminosity (via slight increases in temperature and radius), which is termed radiative ...

  3. Exponential growth - Wikipedia

    en.wikipedia.org/wiki/Exponential_growth

    After one hour, or six ten-minute intervals, there would be sixty-four bacteria. Many pairs (b, τ) of a dimensionless non-negative number b and an amount of time τ (a physical quantity which can be expressed as the product of a number of units and a unit of time) represent the same growth rate, with τ proportional to log b.

  4. Biological exponential growth - Wikipedia

    en.wikipedia.org/wiki/Biological_exponential_growth

    Resource availability is essential for the unimpeded growth of a population. Examples of resources organisms use are food, water, shelter, sunlight, and nutrients.[1][2] Ideally, when resources in the habitat are unlimited, each species can fully realize its innate potential to grow in number, as Charles Darwin observed while developing his theory of natural selection.

  5. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites

  6. Evolutionary history of plants - Wikipedia

    en.wikipedia.org/wiki/Evolutionary_history_of_plants

    Land plants evolved from a group of freshwater green algae, perhaps as early as 850 mya, [3] but algae-like plants might have evolved as early as 1 billion years ago. [2] The closest living relatives of land plants are the charophytes, specifically Charales; if modern Charales are similar to the distant ancestors they share with land plants, this means that the land plants evolved from a ...

  7. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    Fossils of what are thought to be filamentous photosynthetic organisms have been dated at 3.4 billion years old. [60] [61] More recent studies also suggest that photosynthesis may have begun about 3.4 billion years ago, [62] [63] though the first direct evidence of photosynthesis comes from thylakoid membranes preserved in 1.75-billion-year-old ...

  8. The scientific reason years get faster as we get older – and ...

    www.aol.com/scientific-reason-years-faster-older...

    For a four-year-old, a year is a much bigger percentage of their overall lifespan thus far than it is for a 40-year-old – so no wonder it feels longer and more significant. When we’re young ...

  9. Evolution of photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_photosynthesis

    2.4 – 2.3 billion years ago Earliest evidence (from rocks) that oxygen was in the atmosphere 1.2 billion years ago Red and brown algae become structurally more complex than bacteria 0.75 billion years ago Green algae outperform red and brown algae in the strong light of shallow water 0.475 billion years ago First land plants – mosses and ...