Animal Evolution Lecture Notes Review

Flashcards extracting key information from a lecture on animal evolution, covering topics from basic animal characteristics to the timeline of animal diversification. These flashcards aim to help review the phylogenetic relationships, major evolutionary events, and factors influencing diversification and extinction.

What is one school of thought in evolutionary biology regarding form and function?

The function of an organism is dictated by the evolution of its form.

What is the second school of thought in evolutionary biology regarding form and function?

There is some sort of function that is required or that is something that might be better naturally selected for, and therefore the organism evolves a structure or its form to fit or best fit that function.

What are some characteristics that generally define an animal?

Multicellular, heterotrophic, internal digestion, nervous system, and involuntary movement.

How do animals obtain nutrients?

Animals have to be able to consume, extract, and absorb their nutrients because they are internal heterotrophs.

How do animals obtain and deliver oxygen?

Animals obtain oxygen and have mechanisms to deliver that oxygen to all the tissues and cells that require it.

What has to be removed from cells?

Waste has to be removed from the cell

What is necessary for everything to occur?

To survive and reproduce.

What types of symmetry do animals possess?

Radial symmetry or bilateral symmetry.

What are the different types of body cavities that animals might possess?

Coelomates, pseudocoelomates, and acoelomates.

What does the segmentation of animals have to do with?

The division of the body into different types of segments, where different segments can have different appendages that evolve over time to be derived from those particular segments.

What are the two major forms of digestive systems in animals?

A sac-like structure and a tube-like structure.

What are acoelomates?

Organisms that have no true coelom or fluid-filled enclosed body cavity housing organ systems.

What are pseudocoelomates?

They possess a coelom (fluid-filled space), but there's no true connective tissue membranes separating the organs.

What are coelomates?

They have that added layer of mesoderm that is separating and compartmentalizing those organ structures.

What molecules allow for cell adhesion ensuring multicellularity in animals?

Cell adhesion molecules (CAMs) and integrins.

What does Centralization in animal evolution mean?

Sensory structures have evolved to be oriented more towards the anterior or the head region of the organism.

What is the closest relative to all animals?

The choanoflagellates.

What took place during the Cambrian period (540 million years ago)?

There was this explosion of animal diversity.

What does it mean that during the Cambrian explosion?

Most of the modern animal phyla that we see had already appeared at this point in the fossil record.

What is Punctuated equilibrium?

The animal had slow diversification and then a short, sudden quick period or burst of rapid diversification.

What factors helped the explosion of animal diversity?

A relatively massive and rapid increase in the globally available oxygen and a massive increase in the available ocean calcium.

What was the effect of an expansive continental shelf?

Increase habitat, shallow habitat, warmer habitat.

What genes allow for rapid diversification?

Hox genes.

After the Cambrian period, plants colonized land. What did allow?

Plants colonizing the land first.

What comes after the Cambrian.

During this time, plants actually colonize land and Then animals colonize land.

What important things evolved that led the first radiation of fishes colonization in the Ordovician?

Spinal Column.

What developed towards the end of the carl Ordovician for fishes?

The armored plates.

What two different major lineages of fishes?

The cartilaginous fishes and The bony fishes.

What is following to the early shark fish lineage?

That's called the Devonian.

What animals started to get evolved?

The lung fishes, all these different intermediates that where look fish.

Whats happened with an animal that it wiped out in extinction events.

It wipes up a big portion of animals and those have extinction event is they basically start reading any occupying.