Lecture 19 Flashcards
What evolutionary advantage does an endoskeleton provide vertebrates?
A4: It allows for a larger body size and supports segmented muscles for complex movement
Name and describe two early vertebrate fossils found in China.
Myllokunminigia (518 mya) with cranium segments, and Haikouichthys (518 mya) with cartilaginous gill supports; both are from the Chengjiang fauna.
Describe the difference between proactive and reactive conservation.
Proactive conservation involves actions to prevent extinction before species are at high risk, while reactive conservation focuses on species already in decline.
Explain the significance of the IUCN Red List.
The IUCN Red List categorizes species based on their conservation status, helping prioritize species that are at risk of extinction.
: What are ostracoderms and during what period did they exist?
Early jawless fish with bony armor, existing from the Ordovician to Devonian periods
What are the evolutionary origins of vertebrates?
Vertebrates originated from early species like Myllokunminigia and Haikouichthys, both found in Chengjiang fauna, China.
What are the main parts of the vertebrate brain and their functions?
Forebrain (olfactory system), Midbrain (ocular system), Hindbrain (balance, hearing, taste, touch, respiration, circulation).
What unique feature do vertebrates have that leads to a tri-partite brain?
The neural crest, which is quadroblastic.
What is needed for successful species conservation?
Proactive efforts, maintaining healthy and genetically diverse populations, and ecological resilience.
What percentage decline has been seen in vertebrate populations from 1970 to 2014?
A 60% overall decline.
What are some examples of human-induced vertebrate extinctions?
Pleistocene megafauna in Australia, mastodons, mammoths, giant sloths, and species like the Moa bird and the Dodo.
What is the Holocene extinction?
The current period of species decline, possibly the sixth mass extinction, with significant declines in wild mammals, marine mammals, and fish.
Name the five historical mass extinctions.
Ordovician, Devonian, Permian, Triassic, and Cretaceous.
What is the IUCN Red List?
A list of threatened species aimed at identifying species that need protection
Why is biodiversity important?
It’s crucial for conservation and ecosystem balance, helping species adapt to new diseases and climate changes.
