BIO 202 - Animal Biodiversity - Spring 2023 - Lectures 1 & 2

Flashcards about animal biodiversity, origin of life, and evolution.

What defines life?

Something that metabolizes, grows, and reproduces.

What are the ways humans gain knowledge?

Experiential, religious, and scientific methods.

Who calculated the age of the Earth to be approximately 6000 years?

Archbishop Ussher in the 1640s.

What was the 1800s belief about the origin of life from non-living matter called?

Spontaneous generation.

Who proposed the 'Primordial soup hypothesis'?

A.I. Oparin and J.B.S. Haldane.

How do we estimate the age of the Earth?

Radiometric dating of minerals in igneous rocks, meteorites, and moon rocks.

What geological process explains why not all igneous rocks on Earth are the same age?

Plate tectonics.

Where do we get clues about the early Earth's conditions?

Volcanoes and other planets.

What were the primary energy sources on early Earth?

Radioactive, electrical, UV, and geothermal energy.

Who conducted the 'Miller-Urey experiment'?

Stanley Miller.

What did the Miller-Urey experiment demonstrate?

Formation of building blocks of life (amino acids, fatty acids, adenine).

Where might processes that led to the origin of life have been enhanced?

Hydrothermal vents.

What type of organisms were the earliest life forms?

Non-photosynthetic, anaerobic bacteria.

What metabolic process did early life use to degrade organic molecules?

Anaerobic fermentation.

What type of bacteria originated photosynthesis and produced oxygen?

Photosynthetic anaerobic bacteria (cyanobacteria).

What geological formations resulted from the reaction of iron with oxygen produced by early photosynthetic organisms?

Banded iron formations (Fe2O3).

What acted as an 'oxygen-sponge' and absorbed oxygen for over a billion years?

Iron.

What types of organisms evolved as a result of increasing oxygen levels?

Aerobic heterotrophs and aerobic autotrophs.

What major evolutionary events occurred between 1.8 and 1.4 billion years ago?

Oxidative metabolism, eukaryosis, advent of sex, and biodiversity increase.

What evidence supports the evolution of eukaryotes from prokaryotes?

Mitochondria and chloroplasts retain genetic material.

What are the key processes involved in the origin of sex?

Reduction division (meiosis) and recombination.

What major evolutionary events occurred between 700 and 540 million years ago?

Origin of metazoa, Ediacaran fauna, O2 levels surpass 10%, Cambrian 'explosion'.

What hypothesis explains the origin of metazoa from protists?

Colonial Flagellate Hypothesis.

What are the characteristics of Stage 1 of the Cambrian Period?

Soft bodies, imprints in mudstone, oxygen below 5%.

What are the characteristics of Stage 2 of the Cambrian Period?

Hard part fossils, oxygen above 5%, ~34 phyla from this point onward.

What are the three major eras in the history of animal life?

Paleozoic, Mesozoic, and Cenozoic.

Which global mass extinction event killed ~96% of species?

End Permian period.

What caused the mass extinction at the end of the Cretaceous period?

Chicxulub impactor.

What is the name of the current extinction event?

Holocene extinction.

Approximately how many phyla of animals are there?

~34

When did all animal phyla evolve?

Ediacaran/Cambrian (~600-500 mya).