What are chimaeras?
Q: What are chimaeras?
A: Chimaeras are cartilaginous fish in the order Chimaeriformes, also known as 'ghost sharks'.
Q: What is special about chimaeras in terms of their evolution?
A: Chimaeras branched off from sharks nearly 400 million years ago and have remained isolated ever since, making them one of the oldest and most enigmatic groups of fishes alive today.
Q: How diverse and abundant were chimaeras in the past?
A: Chimaeras were once a diverse and abundant group, as shown by the fossil record.
Q: Where are chimaeras mainly found nowadays?
A: Chimaeras are now found mainly in deep water.
Q: How many living species of chimaeras are there, and in how many families?
A: There are fifty living species of chimaeras in six genera and three families.
Q: Why has studying the evolution of chimaeras been problematic?
A: Studying the evolution of chimaeras has been problematic because there are few good fossils.
Q: What is the preferred approach to understanding speciation in chimaeras?
A: DNA sequences have become the preferred approach to understanding speciation in chimaeras.
