How to Create a New Species

The story of how one species of lizard became two.

Act I: Isolation

Once upon a time, there were two types of lizards

A new river formed and the two sides were separated

Some lizards survived and others died

The lizards that survived, reproduced and passed on their traits

Thousands of years later

Act II: Speciation

There were two types of green lizards

The larger lizards were able to compete for food and survived

The larger lizards, reproduced and passed on their traits

Thousands of years later, there were two SPECIES of lizards

Same Species?

Vocabulary

• Speciation

– Formation of a new species through isolation

– New species cannot reproduce with the old one

5 million years ago, there used to be one species of snapping shrimp before the Panama isthmus was formed. Now there are two species of snapping shrimp that will snap at each other but will not mate. How did this happen?

Speciation Practice A

Vocabulary

• Geographic Isolation

– When a population is physically separated into two smaller populations resulting into two new species

– Ex. Lizards separated by river OR snapping shrimp separated by isthmus

The queen bee uses a mating ritual to start a new hive. She flies in an upward spiral in the air and the males must follow her until one can catch up and the others aren’t able to make it. A wasp queen sits on a flower and waits for males to fly by and attracts them using a scent they release into the air. Why can’t a male bee mate with a female wasp? Why can’t a male wasp mate with a female bee?

Speciation Practice B

Vocabulary

• Behaviorial Isolation

– When a population is separated by behavior (mating time or mating rituals) into two smaller populations resulting into two new species

– Ex. Wasp and bee mating behaviors

Challenge Questions

1. What are other ways that members of the same species could become isolated so that they could no longer reproduce?

– Hint #1: think of how song birds reproduce

– Hint #2: think of seasonal flower blooms

2. How are these different from the type of speciation that we saw in the story?