Ch. 5 continued 1 Classification systems Evolutionary Systematics: - - PowerPoint PPT Presentation

• Ch. 5 continued

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Evolutionary Systematics: explains ancestor-descendant relationships over time. Cladistics: uses shared derived traits to classify new species.

• No time dimension.

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Classification systems

Homologies

Homologies: similarities between groups due to common descent. Derived traits: modified from the ancestral conditions.

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Macroevolutionary processes

Adaptive radiation: rapid expansion and diversification of groups into empty niches. Niche: a species' place in an environmental setting.

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Generalized vs specialized traits

Generalized: adapted for many functions. Specialized: traits specialize to niches.

• Arise during adaptive radiation.

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Fossil: remains of an organism preserved over time

*Mineralization: organic material is chemically turned into rock.

*Mineralization: organic material is chemically turned into rock. *Organisms are trapped in tree resin/an anoxic environment. *Imprints: tracks or leaves hardened in mud.

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Fossil: remains of an organism preserved over time

Paleozoic era (570-225 mya)

• first vertebrates emerged
• first mammal-like reptiles
• Pangaea formed

Mesozoic era (225-65 mya)

• Age of dinosaurs

Cenozoic era (65-0 mya)

• Age of mammals

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Video question

Attendance: Write your name on a piece of paper and do the following: Identify at least three examples of the different concepts discussed in the course so far. Ex: Homologies, mitosis, meiosis, natural selection, genetic drift, gene flow (migration), mutation, etc. https://youtu.be/StqZI9pMq0U?t=223

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