The Holocene extinction, or Anthropocene extinction, is the ongoing extinction event caused by humans during the Holocene epoch. These extinctions span numerous families of plants and animals, including mammals, birds, reptiles, amphibians, fish, and invertebrates, and affecting not just terrestrial species but also large sectors of marine life. With widespread degradation of biodiversity hotspots, such as coral reefs and rainforests, as well as other areas, the vast majority of these extinctions are thought to be undocumented, as the species are undiscovered at the time of their extinction, which goes unrecorded. The current rate of extinction of species is estimated at 100 to 1,000 times higher than natural background extinction rates and is increasing. During the past 100–200 years, biodiversity loss and species extinction have accelerated, to the point that most conservation biologists now believe that human activity has either produced a period of mass extinction, or is on the cusp of doing so. As such, after the "Big Five" mass extinctions, the Holocene extinction event has also been referred to as the sixth mass extinction or sixth extinction; given the recent recognition of the Capitanian mass extinction, the term seventh mass extinction has also been proposed for the Holocene extinction event.
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic, species, and ecosystem level. Biodiversity is not distributed evenly on Earth; it is usually greater in the tropics as a result of the warm climate and high primary productivity in the region near the equator. Tropical forest ecosystems cover less than 10% of earth's surface and contain about 90% of the world's species. Marine biodiversity is usually higher along coasts in the Western Pacific, where sea surface temperature is highest, and in the mid-latitudinal band in all oceans. There are latitudinal gradients in species diversity. Biodiversity generally tends to cluster in hotspots, and has been increasing through time, but will be likely to slow in the future as a primary result of deforestation. It encompasses the evolutionary, ecological, and cultural processes that sustain life.
Extinction is the termination of a taxon by the death of its last member. A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" after a period of apparent absence.
Overconsumption describes a situation where a consumer overuses their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this may be described as the point where the marginal cost of a consumer is greater than their marginal utility. The term overconsumption is quite controversial in use and does not necessarily have a single unifying definition. When used to refer to natural resources to the point where the environment is negatively affected, it is synonymous with the term overexploitation. However, when used in the broader economic sense, overconsumption can refer to all types of goods and services, including manmade ones, e.g. "the overconsumption of alcohol can lead to alcohol poisoning". Overconsumption is driven by several factors of the current global economy, including forces like consumerism, planned obsolescence, economic materialism, and other unsustainable business models and can be contrasted with sustainable consumption.
Conservation biology is the study of the conservation of nature and of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction and the erosion of biotic interactions. It is an interdisciplinary subject drawing on natural and social sciences, and the practice of natural resource management.
Julian Lincoln Simon was an American economist. He was a professor of economics and business administration at the University of Illinois from 1963 to 1983 before later moving to the University of Maryland, where he taught for the remainder of his academic career.
Paul Ralph Ehrlich is an American biologist known for his predictions and warnings about the consequences of population growth, including famine and resource depletion. Ehrlich is the Bing Professor Emeritus of Population Studies of the Department of Biology of Stanford University, and President of Stanford's Center for Conservation Biology.
The Anthropocene is a proposed geological epoch dating from the commencement of significant human impact on Earth's geology, landscape, limnology and ecosystems, including, but not limited to, anthropogenic climate change. The nature of the effects of human activities on Earth can be seen for example in biodiversity loss, climate change, biogeography and nocturnality parameters, changes in geomorphology and stratigraphy.
An ecological or environmental crisis occurs when changes to the environment of a species or population destabilizes its continued survival. Some of the important causes include:
Human impact on the environment refers to changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans. Modifying the environment to fit the needs of society is causing severe effects including global warming, environmental degradation, mass extinction and biodiversity loss, ecological crisis, and ecological collapse. Some human activities that cause damage to the environment on a global scale include population growth, neoliberal economic policies and rapid economic growth, overconsumption, overexploitation, pollution, and deforestation. Some of the problems, including global warming and biodiversity loss, have been proposed as representing catastrophic risks to the survival of the human species.
Ecosystem services are the many and varied benefits to humans provided by the natural environment and healthy ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystem, grassland ecosystems, and aquatic ecosystems. These ecosystems, functioning in healthy relationships, offer such things as natural pollination of crops, clean air, extreme weather mitigation, and human mental and physical well-being. Collectively, these benefits are becoming known as ecosystem services, and are often integral to the provision of food, the provisioning of clean drinking water, the decomposition of wastes, and the resilience and productivity of food ecosystems.
Gene banks are a type of biorepository that preserves genetic material. For plants, this is done by in vitro storage, freezing cuttings from the plant, or stocking the seeds. For animals, this is done by the freezing of sperm and eggs in zoological freezers until further need. With corals, fragments are taken and stored in water tanks under controlled conditions. Genetic material in a 'gene bank' is preserved in a variety of ways, such as freezing at -196 °C in liquid nitrogen, being placed in artificial ecosystems, or put in controlled nutrient media.
Human overpopulation describes a concern that human populations may become too large to be sustained by their environment or resources in the long term. The topic is usually discussed in the context of world population, though it may concern individual nations, regions, and cities.
Global biodiversity is the measure of biodiversity on planet Earth and is defined as the total variability of life forms. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 2 million to 1 trillion, but most estimates are around 11 million species or fewer. About 1.74 million species were databased as of 2018, and over 80 percent have not yet been described. The total amount of DNA base pairs on Earth, as a possible approximation of global biodiversity, is estimated at 5.0 x 1037, and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).
Enric Sala is a former university professor who saw himself writing the obituary of ocean life, and quit academia to become a full-time conservationist as a National Geographic Explorer-in-Residence. Sala’s present goals are to help protect critical marine ecosystems worldwide, and to develop new business models for marine conservation. He also produces documentary films and other media to raise awareness about the importance of a healthy environment, and to inspire country leaders to protect more of the natural world.
Parataxonomy is a system of labor division for use in biodiversity research, in which the rough sorting tasks of specimen collection, field identification, documentation and preservation are conducted by primarily local, less specialized individuals, thereby alleviating the workload for the "alpha" or "master" taxonomist. Parataxonomy may be used to improve taxonomic efficiency by enabling more expert taxonomists to restrict their activity to the tasks that require their specialist knowledge and skills, which has the potential to expedite the rate at which new taxa may be described and existing taxa may be sorted and discussed. Parataxonomists generally work in the field, sorting collected samples into recognizable taxonomic units (RTUs) based on easily recognized features. The process can be used alone for rapid assessment of biodiversity.
Gretchen C. Daily is an American environmental scientist and tropical ecologist. She has contributed to understanding humanity's dependence and impacts on nature, and to advancing a systematic approach for valuing nature in policy, finance, management, and practice around the world. Daily is co-founder and faculty director of the Natural Capital Project, a global partnership that aims to mainstream the values of nature into decision-making of people, governments, investors, corporations, NGOs, and other institutions. Together with more than 300 partners worldwide, the Project is pioneering science, technology, and scalable demonstrations of inclusive, sustainable development.
Biodiversity loss happens when various species disappear completely from Earth (extinction) or when there is a decrease or disappearance of species in a specific area. This in turn leads to a reduction in biological diversity in that area. The decrease can be temporary or permanent. It is temporary if the damage that has led to the loss is reversible in time, for example through ecological restoration. If this is not possible then the decrease is permanent. This ongoing global extinction is a biodiversity crisis. The cause for most of the biodiversity loss are those human activities that push the planetary boundaries too far.
John Harte is an American ecologist and Professor of the Graduate School in the Energy and Resources Group at the University of California at Berkeley. His work includes investigation into a maximum entropy theory of ecology and long-term experiments on the effects of climate change on alpine ecology.
Maria Dornelas FRSE is a researcher in biodiversity and professor of biology based at St. Andrew's University. She was made a Fellow of the Royal Society of Edinburgh in 2021. Her research into biodiversity change has challenged previous views, on the growth and decline of coral reefs to understanding global biodiversity with data analysis on how species or ecosystems are changing in the Anthropocene.
