The number of births in China in 2015: policy meets superstition

Human PopulationThe human population is the total number of people living on Earth, and it’s been growing quickly! As more people are born, we need more food, water, energy, homes, and jobs. Humans have developed incredible technology and systems to support this growth, but it can also cause problems like pollution, climate change, and less room for wildlife. By learning about how the population changes, you can better understand how people affect the planet and explore ways to live more...

Population Growth PatternsPopulation growth patterns show how the size of a group of living things changes over time. These patterns can increase, decrease, or stay the same depending on different factors. When birth rates exceed death rates, the population increases as more individuals are born than die. If more die than are born, the population shrinks. Other important factors include food, water, and space availability, and whether the environment is safe and healthy. Changes in weather,...

Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced...

Mammal ReproductionMammals have specialized reproductive strategies that set them apart from other vertebrates. Most mammals give birth to live young (except monotremes like the platypus and echidna, which lay eggs) and provide care for their offspring. One key feature of mammals is that mothers produce milk to feed their young through mammary glands. Mammals also show various parental care behaviors that increase the survival chances of their young, such as protecting, feeding, and teaching...

Vasectomy is a surgical form of male sterilization that involves severing and sealing the vasa deferentia, preventing sperm from mixing with semen during ejaculation. Because a vasectomy does not impact the testes' ability to produce testosterone, hormone levels, libido, and sexual function generally remain unchanged. While vasectomy is highly effective in preventing pregnancy, with a success rate near 99.85%, rare cases of recanalization (spontaneous reconnection) can occur. Although...

Patterns of Energy ConsumptionEnergy consumption refers to the way people and countries use energy for daily activities such as heating, transportation, manufacturing, and technology. Patterns of energy use vary worldwide based on factors like population size, industrial development, climate, and access to resources. By studying these patterns, we can understand how energy is used, identify which sources are relied on the most, and explore how energy use impacts the environment.Energy...