Prehistoric Life: Paleolithic and Neolithic Eras
The first prehistoric humans: During the Paleolithic era, it was a time of great change due to the old ice age. Humans had to adapt to survive. They relied on gathering fruit, fishing, and hunting. They were primarily hunters of large predators such as bison, mammoths, and deer.
During this time, humans lived in caves and shelters for protection from the heat. They used materials like leather and clay to build their homes. They were nomads, constantly moving to find food, shelter, or escape dangers.
Read MoreFrancoism in Spain: Politics, Economy, and Society Until 1959
Francoism: Political, Economic, and Social Aspects Until 1959
The Rise of a New State
Following the victory in the Civil War, a new state was preferentially established on the 18th of July, defending the interests of the dominant classes and a conception of order against perceived threats like social chaos, communism, and anti-Catholicism. The state, under a single command, concentrated all power in a military dictatorship, led by Francisco Franco. This dictatorship strongly opposed the ideals of
Read MoreHuman Ancestry: A Timeline of Key Species and Discoveries
Human Evolution: From Australopithecus to Homo Sapiens
Key Hominid Species
- Australopithecus: 4.5 – 1.5 million years ago (Ma). The first species with clearly human characteristics.
- Homo habilis: 2.5 – 1.5 Ma. The first tool builders.
- Homo erectus: 1.8 – 0.2 Ma. The first hominids to leave Africa and use fire.
- Homo heidelbergensis: 0.5 Ma – 50,000 years ago.
- Homo neanderthalensis: 0.2 Ma – 25,000 years ago. A European species that lived alongside Homo sapiens.
- Homo sapiens: Appeared about 150,000 – 200,
Secondary Sector: Industry, Mining, and Energy in Spain
Secondary Sector: Industry, Mining, and Energy
Activities and Origins of Raw Materials
The secondary sector is the economic sector with activities that transform raw materials into finished products. This includes industry, mining, and energy sources. There are three origins of raw materials:
- Animal: meat and milk
- Vegetable: wood and fruits
- Mineral: metal and rocks
Minerals
Minerals can be classified as:
- Metallic: Contains metals that can be extracted (e.g., gold, iron, lead)
- Non-metallic: Do not contain
Continental Drift, Plate Tectonics, and Geological Processes
Continental Drift Theory
About 200 million years ago, the continents were united into a single landmass called Pangea, surrounded by a sea called Panthalassa. This supercontinent fragmented, and the pieces began to drift to their current positions. This theory was proposed by Alfred Wegener in 1912.
Convection Currents Theory
Convection currents are a powerful engine for moving continents. These currents are movements of materials caused by differences in density due to temperature variations. The
Read MoreRenewable Energy and Sustainable Technologies: A Comprehensive Analysis
Air Exchange Rate
Air exchange rate is the rate at which outdoor air replaces indoor air within a defined space. It is a measure of ventilation effectiveness and is often expressed as the number of air changes per hour, which represents how many times the entire volume of air is replaced with fresh air in an hour. AER = Fresh air supply / volume of room.
Heat Sources for Buildings
- Heating systems: Furnaces, boilers, heat pumps
- Solar energy: Harnessed through solar panels or passive systems
- Electrical