DNA and Dung Beetles

TL;DR

Scientists propose cataloguing all living things on Earth by the end of the century, with estimates of around 5 million species, not 100 million.

Transcript

hi I'm Emily graslie of the brain scoop filling in for Hank green sorry I know you really liked Michael Aranda last week but it's my turn now and you are indeed in the right place because this is scishow news and there's a lot we have to lay on you today an effort to classify every organism on earth a fight among scientists about what happened in t... Read More

Key Insights

• 🧑‍🔬 Scientists propose cataloging all living things on Earth by 2100, estimating about 5 million species.
• ☠️ The extinction rate for known species is lower than feared, indicating that species are not disappearing at an alarming rate.
• 👶 The science of taxonomy is thriving, with an average of 18,000 new species being discovered and classified each year.
• 🙂 Dung beetles are the first animals known to navigate by the light of the Milky Way.
• 🧑‍🔬 Earth experienced a massive burst of radiation in the 8th century, but scientists are still debating the cause.
• 🥶 Unusually high levels of radioactive carbon-14 and beryllium 10 were detected in ancient cedar trees and ice cores, suggesting intense radiation.
• 💥 Possible causes for the radiation event include a coronal mass ejection from the Sun or a collision between two supermassive objects in our galaxy.

Questions & Answers

Q: Why have scientists previously believed it would be impossible to catalog all living things on Earth?

Scientists believed there were too many species to discover and that many unknown species could be going extinct before they are found. Additionally, taxonomy was not seen as an attractive discipline for many researchers.

Q: How do biologists estimate the number of species on Earth?

Biologists argue that there are likely around 5 million species on Earth, not 100 million as previously thought. They suggest that about 20% of known species are duplicates, mistakenly classified as separate species.

Q: What is the current extinction rate for known species?

The extinction rate for known species averages less than 5% per decade, according to the biologists. This suggests that species are not disappearing as quickly as some fear.

Q: Where do most of the new species discoveries occur?

Most new species discoveries occur in biodiversity hotspots, especially in South America and the Asia Pacific region.

Summary & Key Takeaways

• Biologists propose that it is possible to classify all living things on Earth by 2100, estimating there are around 5 million species, not 100 million as previously thought.

• They argue that the extinction rate for known species is less than 5% per decade, suggesting that species are not disappearing as rapidly as feared.

• The science of taxonomy is thriving, with an average of 18,000 new species being discovered and classified each year.