Pre-hominid human evolution all the way back to LUCA.
320,000 Generations Ago Last Gorilla-Chimp-Human ancestor: The last common ancestor of gorillas, chimpanzees, and humans likely lived about 8 to 10 million years ago. Both the Nakalipithecus and Chororapithecus genuses are candidates. Genus Nakalipithecus: This “might” be the leading plausible candidate. From Kenya, they are dated to about 10 million years ago. Location: Emerged in Western […]
Gorillas Branch Off: Genus Nakalipithecus Read More »
2,600 Generations Ago (from 2020 CE) Long before the sails of European explorers dotted the horizon, the Australian continent witnessed the arrival of its first human inhabitants. Archaeological evidence, such as ancient tools and cave art, suggests that people arrived in Australia at least 65,000 years ago, marking one of the earliest known human migrations
The Settlement of Australia Read More »
30 Phil, Chapter 1 Touchstone 1 of 80: Big Bang. Immediately following the state of the singularity, the universe entered a phase of rapid expansion and cooling, known as the Big Bang Expansion. This critical period signifies not an explosion in space but the very expansion of space itself, from an incomprehensibly dense point known
Big Bang Expansion Read More »
Following the appearance of self-replicating molecules, the RNA world hypothesis suggests a period where RNA served both as genetic material and as a catalyst for chemical reactions. This phase emphasizes the central role of RNA in early life forms, prior to the evolution of DNA and proteins. The RNA world could be considered both a
Between the development of metabolic pathways and the formation of cellular membranes, there might have been a phase involving the assembly of protocells. These protocells, formed from self-assembled lipid molecules creating vesicles, could encapsulate nucleic acids and metabolic molecules, offering a primitive model for cell-like structures. Protocells represent a bridge between non-living chemical systems and
Assembly of Protocells Read More »
Alongside or following the chemical evolution of organic molecules, the formation of prebiotic microenvironments, such as hydrothermal vents or warm little ponds, provided niches where concentrations of organic molecules could interact. These environments could have been crucial for the assembly of complex organic molecules and the initiation of catalytic cycles.
Formation of Prebiotic Microenvironments Read More »
While the 4.4 billion years ago is a guess as to when these processes might have started, the 4.1 billion years ago guess is a better representatoin of current understanding on when the needed building blocks of life evolved. Before the appearance of self-replicating molecules, there was a crucial phase of chemical evolution where simple
Chemical Evolution of Organic Molecules Read More »
The appearance of self-replicating molecules, such as RNA or similar nucleic acid analogues, signified a monumental leap towards life. These molecules had the ability to store genetic information and catalyze their own replication, laying the foundational mechanism for heredity and evolution by natural selection, driving the complexity forward towards the emergence of life as we
First Life: Self-Replicating Molecules Read More »
The formation of cellular membranes represents a pivotal development in the pre-life world, enabling the creation of defined boundaries for primitive cells. These membranes, likely formed from simple lipid bilayers, provided a controlled environment for chemical reactions and played a critical role in the emergence of the first cell-like structures, distinguishing them from their surrounding
Cellular Membranes Read More »
Before the diversification of life, the establishment of basic metabolic pathways marked a crucial step towards biochemistry that supports life. These pathways allowed the conversion of inorganic and simple organic molecules into more complex compounds, setting the stage for energy transfer and the synthesis of key biomolecules necessary for cellular processes.
Metabolic Pathways Read More »
First Prokaryotes: They evolved from replicating molecules and before LUCA (also a prokaryote). Prokaryotes lack a nucleus and organelles. Although research continues identifying when the first true prokaryotes evolved, it is believed they evolved sometime between 3.8 to 4 billion years ago. While the earliest prokaryotes are part of our direct-line ancestors, today we know
76,000 Generations Ago Homo erectus is a direct ancestor of modern humans and represents a key point in human evolution where evidence of a truly omnivorous diet becomes clear, including the use of tools for hunting and processing both plant and animal foods. This species shows significant brain enlargement and other adaptations indicative of complex
Homo erectus: A True Omnivore Read More »
Both reptiles and our ancestor synapsids evolved from amphibians. While reptiles evolved better amniotic eggs, synapsid eggs were like amphibian eggs. Synapsid’s birthing process eventually led to mammalian live births. These are the animals that evolved Complex Sentience, the ability to feel various emotions. While it is unknown when this complex spectrum fully evolved, it
Early Complex Sentience Emerges: Dimetrodon Read More »
Morganucodon is an example of a plant eater likely similar to our direct-line ancestors around this time. It is not a direct human ancestor but is among the early mammaliaforms, close to the lineage leading to true mammals. It likely had a varied diet, but its inclusion here highlights the transition towards more specialized mammalian
Morganucodon: An Early Mammalian Herbivore Read More »
Plesiadapis, a proto-primate, is an example of a fruit-insect eater likely similar to our direct-line ancestors around this time. Class: Mammal; Early Primate (Plesiadapiformes) Time Period: Late Paleocene Diet: Likely Frugivorous/Insectivorous
Plesiadapis: First fruit-insect eaters. Read More »
Creatures of this time evolved into fish (us), jellyfish, cephalopods, and arthropods. In the deep waters of the late Precambrian era, the seeds of sentience were sown with the evolution of the earliest common ancestors to later cephalopods and fish. These primordial creatures, equipped with the most basic nervous systems, embarked on the path toward
Presentient Animals Emerge: The Ediacaran Prelude Read More »
Current scholarship generally places the formation of the Milky Way between 200 and 600 million years after the Big Bang, during the period of early galaxy formation that followed the forging of Population II stars. Some of the oldest stars within the Milky Way belong to this Population II category, with estimates for their formation
Birth of the Milky Way Read More »
Current observations, such as those of GN-z11, suggest that galaxy formation began as early as 400 million years after the Big Bang. This galaxy, observed at a redshift of z=11.09, stands as a testament to the rapidity with which the universe’s first structures began to coalesce from the primordial gas. While the detection of GN-z11
The Earth and the other planets formed 4.5 billion years ago from the same cosmic cloud—the primordial material which gave birth to the Sun. The dust and comets—the rocks—were composed largely of hydrogen, ice, carbon, and nitrogen.
Population I stars likely started forming around 8 to 10 billion years ago, with the process continuing to the present day as new star-forming regions develop in galaxies. These third generation stars are composed of the remnants of Population II stars. The majority of the stars adorning the Milky Way today belong to this third
Population I Stars: Like our Sun Read More »
