Understanding Evolution: Homology and Analogy

Similar structures evolved independently:

Analogies

What plant gave rise to broccoli and cauliflower?

Wild mustard

Tetrapod

a vertebrate animal having four feet or legs or leg-like appendages

Bone in Mammal ears are homologous to what in lizards?

jawbones

3 criteria to determine homology or analogy

structure, relationship, development

How could two unrelated flowers have a similar appearance?

they both evolved to have a similar function, like attracting birds

Homology vs. Analogy

Homology: similarity due to shared ancestry Analogy: similarity due to convergent evolution

Thylacosmilus

Lived in South America, marsupial version of the saber toothed tiger (smiledon). Ate giant armadillos.

Smilodon

Pleistocene saber toothed cat

Analogy (biology)

Similarity due to convergent Evolution.

Homology

Similarity in characteristics resulting from a shared ancestry.

Convergent Evolution (Analogy)

Unrelated organisms similar because independently evolved same characters through similar selection pressure

Are the similarities between sharks and dolphins an example of divergent or convergent evolution? Explain.

analogous, they evolved for the same purpose (swimming)

The bowerbird's bower is a phenomenon that exemplifies... a. Genetic drift b. Adaptive selection c. Sexual selection d. Artificial selection e. Inbreeding

bird species in which the males build bower structures for courtship rituals; their courtship begins in early November, continues through late December (Spring in southern hemisphere)

How are a bird and a crocodile homologous?

both take care of their young

Morphology

form and structure of an organism or any of its parts

What did the common ancestor of all modern Tetrapods look like?

like a lizard

What are the 6 Tetrapod Bones?

radius, humerus, ulna, carpals, metacarpals, phalanges

Pax-6 gene

responsible for eye formation in all animals