Science and the Challenges Facing Society
Science and Technology
Science: Systematic way of acquiring knowledge about the natural world.
Technology: Application of scientific knowledge to the interests of humans.
Technological advances are generally based on scientific investigations.
Challenges Facing Science, Technology, and Society
Climate Change
The scientific community's consensus is that climate change is the greatest challenge to science and society.
Climate change poses a significant threat to both humans and the environment.
Climate change refers to alterations that occur in the Earth’s normal climate cycles that are attributable to human activities.
Climate change is primarily due to an imbalance in the carbon cycle.
Normally, carbon is cycled within an ecosystem.
Due to human activities, more carbon dioxide is being released into the atmosphere than is being removed.
Consensus: Climate change and global warming are causing significant changes in Earth's ecosystems.
Throughout the text, climate change will be covered and how it impacts humans.
Biodiversity and Habitat Loss
Biodiversity: Total number and relative abundance of species, variability of their genes, and different ecosystems in which they live.
Estimated biodiversity of our planet: Around 8,700,000 species (excluding bacteria).
Approximately 2,300,000 have been identified and named.
Extinction: Death of a species or larger classification category.
Estimated current rate of species loss: Hundreds of species per year due to human activities.
Approximately 27% of all identified species (including most primates, birds, and amphibians) may face extinction by the end of the century.
Extinctions are often accelerated by habitat loss and climate change.
Many biologists suggest the present rate of extinction could eventually rival the rates of the five mass extinctions that occurred during our planet's history.
Last mass extinction: Sixty-five million years ago, resulting in the extinction of many plant and animal species, including dinosaurs.
Most Biologically Diverse Ecosystems:
Tropical rainforests
Coral reefs
Ecosystems are threatened by human activity.
Tropical rainforests:
The canopy alone supports a variety of organisms, including orchids, insects, and monkeys.
Coral Reefs: Built up from calcium carbonate skeletons of sea animals called corals, found just offshore of the continents and islands near the Equator.
Reefs provide habitats for many animals: jellyfish, sponges, snails, crabs, lobsters, sea turtles, moray eels, and colorful fishes.
Threats increase as the human population increases
Some reefs are years old, yet human activities have destroyed an estimated 25% of all coral reefs and seriously degraded another 30% in the last few decades.
At this rate, approximately of coral reefs could be destroyed within forty years.
Similar statistics are available for tropical rainforests.
Destruction of healthy ecosystems has many unintended effects.
Food, medicines, and various raw materials are produced by ecosystems and become difficult to acquire.
Draining of natural wetlands of the Mississippi and Ohio rivers and the construction of levees have worsened flooding problems, making once fertile farmland undesirable.
Destruction of South American rainforests has killed many species that may have yielded the next miracle drug and decreased the availability of many types of lumber.
Ecosystems keep chemicals cycling throughout the biosphere.
Ecosystems ensure that the environmental conditions of the biosphere are suitable for the continued existence of humans.
Ecosystems cannot function properly unless they remain biologically diverse.
Emerging and Re-Emerging Diseases
Emerging Diseases: Relatively new to humans such as:
Avian influenza (H5N1 and H7N9)
Swine flu (H1N1)
Severe Acute Respiratory Syndrome (SARS)
Middle East Respiratory Syndrome (MERS)
COVID-19 (caused by SARS CoV-2)
Causes of emerging diseases include:
New or increased exposure to animals or insect populations that act as vectors for disease.
Changes in human behavior and the use of technology.
Example: Legionnaires' disease emerged in 1976 due to bacterial contamination of a large air conditioning system in a hotel.
Globalization results in the transport all over the world of diseases previously restricted to isolated communities.
SARS CoV-2 cases were reported in Wuhan, China, in November 2019. By March 2020, SARS CoV-2 and the respiratory illness it caused, COVID-19, had spread globally and was found in every country and continent on the globe.
As of 2021, COVID-19 had infected over people worldwide and resulted in over deaths.
Pathogens mutate and change hosts, jumping from animals to humans.
Example: Before 1997, avian flu was thought to affect only birds. A mutated strain jumped to humans in the 1997 outbreak.
New forms of avian influenza are being discovered every few years.
The SARS CoV-2 virus is believed to have jumped to humans from horseshoe bats, but other species, such as pangolins, may have been involved.
Re-emerging Diseases: Has been known to cause disease in humans for some time but generally has not been considered a health risk due to a relatively low level of incidence in human populations.
Example: Ebola outbreak in West Africa of 2014-2015.
Ebola outbreaks have been known since 1976, but have generally affected only small groups of humans.
The 2014-2015 outbreak was a much larger event with over people were infected, with over fatalities.
Smaller outbreaks occurred in Africa in 2016 and 2018.
These outbreaks have the potential to disrupt the societies of several West African nations.
Emerging and re-emerging diseases have the potential to cause global health problems for humans, as well as disrupt economies and the structure of human societies.
Scientists investigate:
The causes of these diseases (e.g., viruses).
Their effects on our bodies.
The mechanisms by which they are transmitted.