Module 2: The Evolution (and Coevolution) of Flowering Plants

Course:

• Introductory Biology, Ecology, or Evolution (Freshmen or Sophomores)

Length:

• This exercise is designed as a 3-hour laboratory experience, but activities could be used individually.
• The assessment is completed as a take-home assignment.

Objectives:

• Describe the role of flowers in angiosperm reproduction.
• Identify the parts of a flower.
• Describe the role of fruits in angiosperm reproduction.
• Identify the parts of a fruit.
• Identify different types of fruits.
• Explain the role of pollinators in the life history of angiosperms.
• Define coevolution and identify selection pressures that exist between pollinators and the plants they pollinate.
• Predict pollinator/plant pairs based on morphological traits.
• Collect data from digitized natural history collections.
• Analyze spatial co-occurrence data for pollinators and the plants they pollinate.

Activities:

1. Flower dissection and drawing [30 min] – each pair of students is assigned a flower to dissect and draw.
2. Plant/Pollinator match game [30 min] – each student receives either a pollinator or plant “card” and must locate their match using information provided on the card.
3. Bat/Agave case study using digitized Natural History Collection data [60 min] – students use the iDigBio Portal to investigate the distribution of several bat and plant species to analyze spatial co-occurrence data to make inferences about interspecific interactions.
4. Fruit dissection, drawing, stations [45 min] – each pair of students is assigned a fruit to identify, dissect, and draw. The team then produces a “station” displaying their fruit for other class members to view.

Assessment:

• Students complete a case study assessment investigating the relationship between the early spider orchid (Ophyrs sphegodes) and its pollinator, the solitary bee (Andrena nigroaenea).
• Students use images to identify characteristics of the orchid flower and fruit, use the iDigBio Portal to investigate the co-occurrence of the two species, and write about the selection pressures involved in the co-evolutionary relationship.