How Many Gaps? Author: Judy Scotchmoor

Overview: Evolution is often challenged by those who oppose its teaching or do not understand it. One of these challenges is that “there are gaps in the fossil record.” Ths following little warm-up activity will put that challenge to rest.

Lesson Concepts:

• It is possible to reconstruct the history of life without all of the pieces in place.

Grade Span: 10–16 and teacher workshops

Materials:

• Three cards that read; Pakicetus (~50 mya); Basilosaurus (~ 40mya); Blue Whale; and six cards all of which read Transitional Fossil.

Advance Preparation: none

Time: 5–10 minutes

Grouping: Appropriate for large group discussion

Teacher Background:

We will never discover all of the links in the fossil record. There will always be gaps. In fact, with each new fossil find, we may create a link, but at the same time we will create new gaps! It is possible to reconstruct history without all of the pieces in place.

Vocabulary: transitional fossil

Procedure:

1. Hand one of the first three cards to each of three individuals and ask them to stand up, fairly well spaced apart, facing the rest of the group, displaying their cards.
2. Point to the gaps between the three individuals, noting that there are two gaps.
3. Now give two of the Transitional Fossil cards out to two other individuals. They can then “fill in the gaps!”
4. Now count the gaps. Have four more Transitional Fossil individuals fill in these gaps and lo and behold—how many gaps do we have now? Address the issue that with each new fossil find, more gaps are created, but each “gap” is actually smaller.