This group includes the ancestors of mammals and lived alongside reptiles for millions of years. They eventually died out, except for the lineage that led to mammals.
In the dense, humid forests of the Late Triassic, long before mammals ruled the night, a small, shrew-like creature scurried beneath the ferns. This ancestor—our shared forebear with the platypus—was warm-blooded, fur-covered, and laid soft-shelled eggs. It represents the last moment before the mammalian lineage split: one path leading to the egg-laying monotremes, the other […]
Platypus–Ape Last Common Ancestor Read More »
In more advanced forms, play becomes a complex tool for social bonding, emotional learning, and cognitive development. Carnivores like wolves and cats engage in cooperative games that refine group hunting skills, while elephants are known for their intricate, playful interactions that build emotional connections. Among primates, play takes on its most elaborate forms, fostering problem-solving,
Higher Play Evolves in Social Mammals Read More »
Play in its most basic form likely began as simple, physical interactions aimed at honing survival skills. Modern animals like squirrels, kangaroos, and hedgehogs still exhibit these foundational behaviors, engaging in chasing, pouncing, and wrestling. These actions help young animals develop coordination and reflexes while providing a safe way to practice life-essential tasks. Surprisingly, even
Early Play Evolves in Mammals Read More »
The last common ancestor with humans and old-world monkeys lived around 29 mya. Around 25 to 29 million years ago, Old World monkeys, including species like baboons and macaques, branched off from the common ancestor shared with apes. Unlike their ape cousins, Old World monkeys retained their tails and adapted to a wider range of
Baboons Branch Off: Old World Monkeys Read More »
The last surviving primate before the great apes! Gibbons are a “lesser ape” that branched off from our common ancestor with great apes. By this time, our ancestors had already lost their tails (like all apes) and were very agile in trees, using brachiation (arm-swinging) to move through the canopy. Gibbons are known for their
Gibbons Branch Off: Genus Hylobates Read More »
Around 240 million years ago, during the late Triassic period, a crucial evolutionary development unfolded within the lineage that would give rise to mammals. It is believed that the XX/XY sex-determination system emerged in a common ancestor of mammals, possibly within the genus Therapsida, a group of synapsids that exhibited both reptilian and mammalian traits.
XX/XY Sex System Emerges: A Tale of Mammalian Evolution Read More »
By about 125 million years ago, mammals likely increased their vocabulary above a dozen and perhaps for some species at times into the hundreds. This vocabulary, or signaling, was a series of gestures, grunts, and screeches. Today, mammals from this lineage communicate with a range of signals and gestures, not unlike our abstract vocabulary. We
Animal Vocabulary: Dozens of Words Read More »
Around 60 million years ago, the early ancestors of primates began to develop a crucial adaptation: the opposable thumb. This evolutionary milestone marked the beginning of increased dexterity and the ability to grasp objects more effectively. Living in the dense canopies of prehistoric forests, these early primates used their newly opposable thumbs to navigate their
Opposable Thumb Emerges Read More »
Likely between 25 and 30 million years ago, the evolution of the apes brought about further refinement of the opposable thumb. This period saw the divergence of the lineages that would lead to modern “lesser” apes like gibbons as well as later “great” apes, including orangutans, gorillas, and chimpanzees. The ape thumb evolved to become
Our last comman ancestor of all known great apes lived about 16.5 mya. The orangatan branch split off about 12 mya. After that split the orangatan branch split several more tiimes. The modern orangatan species, the last split of this branch, emerged about 400,000 years ago. Orangutans (genus Pongo) are great apes native to Indonesia
True Primate: Within mammals, only primates have binocular vision, grasping hands, and flat nails–instead of claws. Intelligent: Within the dense forests of the Oligocene epoch, Aegyptopithecus zeuxis marked a significant advance in the evolution of intelligence among primates. As an early forerunner to both the great apes and humans, Aegyptopithecus possessed adaptations crucial for enhanced
Early Intelligence Emerges: Aegyptopithecus zeuxis Read More »
800,000 Generations Ago The last common ancestor with humans and gibbons lived around 20 mya. Great Apes LCA candidate: Proconsul, an inhabitant of the Miocene forests in East Africa, stands as a landmark in the evolutionary journey toward self-awareness. This early ape lacked a tail and exhibited a mixture of arboreal and terrestrial traits, providing
Genus Proconsul (Self-Awareness Settles) Read More »
Emerging in the lush forests of the Eocene, Miacis signifies a pivotal moment in the evolution of cognitive abilities among mammals. As a basal member of the Carnivora, this small, tree-dwelling creature exhibited behaviors and social dynamics suggesting the early stages of self-awareness. Though not akin to the self-recognition seen in humans or other highly
Early Self-Awareness: Miacis Read More »
The rise of Eomaia scansoria, an early placental mammal, marks a definitive leap towards “Complex Sentience” in the evolutionary saga leading to humans. Unearthed from the Early Cretaceous period, Eomaia’s sophisticated array of mammalian features heralds the advent of deeply emotional and social behaviors. Possessing a brain and nervous system capable of supporting complex emotions,
Complex Sentience Settles: Eomaia scansoria Read More »
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 »
As various great ape species fill niche areas around the globe, branches emerge. The last common ancestor of all known great apes, including humans, lived about 16.5 mya. That branch leads to modern orangatans, which split off again about 12.5 mya. The last known split of the modern orangatan was about 400,000 years ago. Orangutan
Orangutans Branch Off: Genus Sivapithecus Read More »
After the split of great apes and humans about 16 mya, and the split of the chimpanzee branch from humans about 7 mya, the two modern pan species split: chimpanzees and bonobos. Around 1.5 to 2 million years ago, the evolutionary branches of ancient primates led to the distinct emergence of what we now recognize
Emergence of the Chimpanzee Family Read More »
An example of early live birth is the protomammal Kayentatherium, Jurassic period. This cynodont is related to early mammals and its clutch size suggested egg-laying, providing clues about the transition to live birth. The switch to live birth in mammals, including marsupials and placentals, likely evolved once at their common ancestor, suggesting live birth in mammals
Mammals: First Live Births 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 »
