Episode 1: Living during a mass extinction
Tree of Life
There are an estimated over 7 million different species of animals on Earth. That includes almost 5,500 species of mammals, almost 10,000 species of birds, 10,000 species of reptile, 15,000 species of amphibians, and astounding 40,000 species of fish. Additionally, by far the largest classification of ‘animal’ are insects and are estimated to have over 7 million different species.
Scientists are now raising the alarm that we are currently in the Earth’s 6th Mass Extinction. The normal extinction rate measured through time estimates approximately 1 mammal (some say 2) should go extinct per century. In just the last 100 years it is estimated that 69 mammals have already gone extinct (that we know of). Therefore, the rates of extinction for all species, to include reptiles, amphibians, fish and other species are accelerating with no signs of slowing down.
Major causes of such a high extinction rate:
- Habitat loss- the rainforests are a clear example. Over 50 football fields of rainforest are cleared every minute around the world.
- Invasive species- humans have accidentally, and in some cases purposely, released animals into environments that are not normally their home. For example, in Florida the large Burmese python (native to Asia) is now living in the Everglades and are hurting native species.
- Climate change- the Earth is getting warmer (fact). It is caused by human activities (fact). In turn, this negatively impacts the environment and native species.
- Over exploitation- human activity has reduced the natural environment to just 25% of what it was just centuries ago.
The All Creatures Podcast’s mission is to educate listeners to the plight of many of the animals facing extinction. Each week we will cover a new species and detail where these animals live, unique aspects of their physiology, what they eat, how they live each day, and what their current status is in nature. Our goal is to not only spread knowledge, we want to develop a community. Listen, Learn, and Share is our motto.
Barnosky. 2011. Has the Earth’s sixth mass extinction already arrived? Nature. 471:51-57.
Ceballos et al. 2015. Accelerated modern human-induced species losses: Entering the sixth mass extinction. Science Advances. 1:e1400253.
McCallum. 2015. Vertebrate biodiversity loss points to a sixth mass extinction. Biodiversity and Conservation. 24:2497-2519.
Cafaro. 2015. Three ways to think about the sixth mass extinction. Biological Conservation. 192:387-393.
Tree of Life. https://www.evogeneao.com/learn/tree-of-life
Habitat loss: AFP PHOTO / Borneo Orangutan Survival Foundation / Jamartin SIHITE