Pre-hominid human evolution all the way back to LUCA.
Likely white or grayish atmosphere: The first atmosphere developed first but was not directly involved in the development of life. The first atmosphere formed shortly after Earth’s formation around 4.5 billion years ago. This initial atmosphere was primarily composed of hydrogen and helium, the lightest and most abundant elements in the universe, which were captured from […]
First Atmosphere: Hydrogen & Helium Read More »
As the Earth cooled following its formation, outgassing from volcanic activity released water vapor and other gases into the atmosphere. When the Earth’s surface cooled sufficiently, this water vapor condensed and fell as rain, filling the basins that would become oceans.
First Oceans: Fresh Water Read More »
The feature of the epicanthic fold, particularly prevalent among East Asian populations descended from Haplogroup A, is an adaptation to cold, windy, and bright environments encountered as humans migrated northward from Africa. This phenotype likely developed to protect the eyes from frostbite and snow blindness, showcasing how genetic diversity within human lineages adapted to specific
Phenotype Variation: Eye Shape and the Epicanthic Fold Read More »
As dairy farming became prevalent, particularly in Europe and some African communities, natural selection favored individuals who could digest lactose into adulthood. This genetic adaptation, known as lactase persistence, is a direct result of human cultural practices (dairying) and has had significant dietary implications.
Phenotype Variation: Lactose Tollerance Read More »
The skin color diversity in primates over the last 20 million years showcases the adaptability of primates. The melanin levels in primate skin vary significantly based on the varying levels of UV radiation exposure in different climates. In high UV regions, darker skin evolved to protect against UV damage and folate degradation, while in areas with
Skin Color Diversity Across and within Primate Species Read More »
Blood type variations originated from common primate ancestors around 20 million years ago. While blood transfusions between species, such as between apes and humans, are not viable due to different and incompatible blood antigens, the development of blood type systems, including types similar to the human A, B, AB, and O, can be traced back
Emergence of Blood Type Variability in Primates Read More »
Homo heidelbergensis was the likely neanderthal-sapiens last common ancestor.
Homo heidelbergensis Read More »
Likely an orangutan ancestor: As the branches of the ape family tree diverged, Dryopithecus emerged during the Miocene epoch, offering a glimpse into the early development of primate social structures. Living approximately 13 to 12 million years ago, this early ape flourished in the European forests, at a time slightly preceding or overlapping with the
Genus Dryopithecus: Cultural Transmission Emerges Read More »
Blue eyes emerging stands out as a striking example of a genetic mutation that spread across populations. Traced back to a single individual living between 6,000 and 8,000 BCE in the region near the Black Sea. The mutation involved is a specific change in the OCA2 gene, which alters the way melanin is produced in
Phenotype Variation: Blue Eyes Read More »
18 Generations Ago 30 Phil, Chapter 20: Francis Bacon and the Scientific Method Francis Bacon was born on January 22, 1561, in London to a prominent and influential family. The young Francis Bacon received a comprehensive education, attending the prestigious Trinity College, Cambridge, at the age of 12. Bacon is the Father of the Scientific
The synthesis of simple organic molecules such as formaldehyde (H₂CO), methanol (CH₃OH), and simple hydrocarbons in the dense molecular clouds of the interstellar medium occured once sufficient carbon was present. This process has been ongoing for billions of years but became more prevalent as the universe aged and more carbon became available. Big History Thresholds:
Interstellar Clouds: Organic Molecules Read More »
The chemical evolution from inorganic precursors to organic molecules is a fascinating story of transformation driven by Earth’s dynamic early conditions and possibly assisted by the input from space in the form of meteorites rich in organic compounds. During this period, the Earth witnessed a series of complex chemical reactions facilitated by its primordial atmosphere,
Inorganic Precursors to Organic Molecules Read More »
Found in Morocco, this natural pebble with human-like features is possibly the oldest known example of a figurine or representation of the human form.
Earliest known symbol use in the Africa/Middle East zone. Located in South Africa, the cave contains engraved ochre pieces, which are among the earliest known forms of abstract art.
Blombos Cave Engravings Read More »
Found in central India, these cupules (circular hollows on rock surfaces) are among the earliest known forms of rock art. They were likely created by a species like Homo erectus or Homo heidelbergensis and not Homo sapiens. Homo sapiens are not known to be in India until around 40,000 years ago. Homo erectus is known
Bhimbetka Petroglyphs, Cupules Read More »
By about 375 million years ago, several animal lineages had evolved long-term memory to navigate a changing world, remembering feeding sites, water access, and safe routes between land and water. This likely included vertebrates like Tiktaalik.
Long-Term Memory Evolves: Tiktaalik Read More »
Chemoreception is older than animals and is found across life, including bacteria, fungi, and plants. Taste and smell evolved later in animals, after the bilaterian split, as early nerve nets and proto-nervous systems gradually gave rise to animal brains that benefited from more specialized information for navigating life. Animal-level chemoreception, the ability to detect chemical
Animal Chemoreception: Proto-Taste and Smell Emerge Read More »
About 3.72 billion years ago, right after LUCA, when cells emerged, touch became the most ancient form of biological sensing: required to physically navigate reality.
Touch: Life Learns to Feel Force Read More »
Hearing, which initially appeared in early fish, underwent a remarkable transformation as vertebrates transitioned to terrestrial life a bit after 400 million years ago. Early forms of hearing involved simple pressure-sensitive cells that could detect vibrations in water. As amphibians moved onto land, rudimentary hearing evolved into processing airborne sound. This transition further drove the
Land Hearing Emerges: Amphibians Read More »
Vision evolved as early as 540 million years ago during the Cambrian explosion. The ability to see, alongside the development of hearing, provided organisms with the evolutionary advantage of sensing their environment from a distance. This sensory evolution necessitated the development of larger brains for the complex processing of visual data, marking a pivotal moment
Vision Emerges: The Pre-fish Chordates Read More »
