Evolution of human brain

INTRO: In the race of survival every organism had to evolve. Evolution in organisms helped to survive in that particular environment. In the case of human beings, evolution helped them a lot . They learned to communicate and work as a team, which helped them to conquer even more powerful animals.

WHAT IS REALLY EVOLUTION?

Evolution is like a long, slow race where living creatures or organisms change little by little over time to help them survive better in their territory. like how some animals grow longer legs to run faster from predators, some develop their brains for critical thinking and some work as a team so that together they can achieve more. It's nature's way of testing out new features to see what works best.

EVIDENCES IN SUPPORT OF ORGANIC EVOLUTION:

Paleontological evidence

Fossils : horse or Equus equus (scientific name of horse), was originated from (Eohippus) often referred to as ‘dawn horse’ . Paleontologists got their evidence from the stone of the Eocene epoch of the Coenozoic era. When the fossils were examined it came out that their height was about 30 cm. They had four fingers on their front legs. This form of horse is called the ‘dawn horse’. From the ‘dawn horse’, ‘up horse’ or the horses that we see in present days took 51-52 million years to evolve. Gradually some general changes can be noticed in the period of evolution. i.e. increase in length of legs, gradual decrease in the number of fingers of leg, Formation of hoof to run on the hard surface of soil. Petrified fossils of horses show gradual improvement in them to survive. So it supports the theory of new arrivals.

EVOLUTION AND ORIGIN OF HUMAN BEINGS :

About 15 million years ago primates called Dryopithecus and Ramapithecus were existing. They were hairy and walked like chimpanzees. Ramapithecus was more man-like while Dryopithecus was more ape-like. Few fossils of man-like bones have been discovered in Ethiopia and Tanzania. This discovery revealed hominid features leading to belief that about 3-4 million years ago, in eastern Africa man-like primates walked in. They used to walk up right and were not taller than 4 feet. They are called the first human-like hominids and were called Homo habilis. The brain capacities were between 650-800cc. They probably did not eat meat. Homo erectus the evolved genus of humans, they had a large brain around 900cc, they probably ate meat. The Neanderthal man with a brain size of 1400cc lived in near East and Central Asia between 1,00,000-40,000 years ago .After that the Homo sapiens, commonly known as modern humans originated in Africa and moved across continents and developed into distinct races.

OBSERVATION ON EVOLUTION OF BRAIN OF VERTEBRATES :

The structure of the brains of vertebrates became complex with evolution. Vertebrates means the animal who has a spine. So the first vertebrate animal was fish. Which originated in water. Then the amphibians evolved from the fishes and then they evolved into reptiles. After that they evolved into birds . And after that mammals (humans) originated from birds. From fishes to mammals. There are 5 common brain structures present.

1. olfactory lobe

2. cerebral hemisphere

3. optic lobe

4. cerebellum

5. medulla oblongata

The cerebral hemisphere of fishes are very small as compared to mammals(mammals mean the animals who have mammary glands, hair and three middle ears bones. Like humans, cats, dogs) . The folding of cerebellum also increased from fish to mammals. On the other hand the olfactory lobe has decreased from fishes to mammals. The structure of the cerebellum of human beings is the most complicated one.

Once the brain evolved, evidence indicates that humans descended from an ancestor similar to chimpanzees. And chimpanzees descended from mammals. Which descended from reptiles and they descended from fish. The bone structure of humans and chimpanzees are related to each other.

The remarkable journey of the human brain: The human brain and an intricate masterpiece. Has undergone a fascinating journey. Today our brains grapple with complex issues: from navigating social dynamics to solving global problems. Our cognitive abilities continue to evolve, adapting to our ever-changing world.