Announcements:
The first Lecture Exam is on Wednesday, Feb. 25th and will be worth 10% of your final course grade. It will cover lectures 1 – 15, text readings, and the first two lecture assignments. For information on how to study and what to do if you miss an exam, click here.
The exam will likely consist of 60 multiple choice questions, similar in style to those presented in your Class Notes. There may also be short answer questions, drawings, and key construction.
As a study guide, view a copy of an old exam by downloading a PDF by clicking here. This year, this same exam is reproduced in the back of your Class Notes (pp. 251-259). Answers will not be posted (click here to find out why). Of course, we will gladly go over your answers with you, should you have concerns.
There is the possibility of a brief lecture review on Monday, Feb. 23, after family coverage has been completed. This will not be a formal review of material, but rather an opportunity for the class to ask questions. So, please come with questions!
Lecture Assignment 2 is due in class on Monday. Assignments handed in after class up to the time of the first lab on Tuesday will receive a 50% deduction, and assignments handed in after lab will not be accepted. Answers will be posted in lab.
Course Objectives:
After studying this material you should be able to:
- Know the most important diagnostic features of these four families and be able to compare and contrast them. For more information on how to study families, refer to Objectives for Plant Families
- List the major clades to which these four families belong and describe their interrelationships.
Readings and Web Resources:
In your textbook Plant Systematics, A Phylogenetic Approach by Judd, Campbell, Kellogg, Stevens, and Donoghue, Third Edition, read the material on these pages:
- Hamamelidaceae, pp. 342 – 344
- Moraceae, pp. 392 – 393
- Fagaceae, pp. 401 – 403
- Betulaceae, pp. 404 – 406
BE SURE to go through these four families in Digital Flowers.
Phylogeny:
We continue coverage of plant families that belong to the Eudicots clade (also called Tricolpate Angiosperms).
The first family we discuss — the Hamamelidaceae — belongs to the order Saxifragales in the Core Eudicots (Core Tricolpates) clade.
The next two families — the Betulaceae and Fagaceae — belong to the order Fagales.
The last family — the Moraceae — belongs to the order Rosales.
The orders Fagales and Rosales along with several other orders comprise the Fabids (or Eurosids I) clade within a larger Rosid clade.
For simplicity, refer to the Betulaceae, Fagaceae and Moraceae as belonging to the Rosid clade, Fabids subclade in the Core Eudicots. The Hamamelidaceae are more distantly related, classified in the Core Eudicots but not in the Rosid clade.
For orientation, see the classification of major angiosperm families in your textbook (Table 9.1, pp. 230-231).
Also, see pages 239-242 in your Class Notes, Classification and Phylogeny of IB 335 Plant Families.
In a previous classification of angiosperms, these four families were treated in the subclass Hamamelidae in three orders.
As we continue coverage of the eudicots clade, notice these features that are more "advanced" that those of the magnoliids.
- tricolpate pollen (or derived from the tricolpate type)
- carpels usually more than one and syncarpous (exceptions occur)
- stamens often numerous, never laminar
Within the four families discussed here — Hamamelidaceae, Moraceae, Betulaceae, and Fagaceae — note the following generalities (with some exceptions in the Hamamelidaceae):
- Most members woody (except Urticaceae, nettle family, related to Moraceae)
- Mostly wind pollinated, flowers generally imperfect, often in catkins
- Generally simple flowers
- "cone-like" fruits
Members of this group were once thought to be the most "primitive" of dicots. We now know that the catkin inflorescence evolved several times and that simple flowers are due to the loss of parts.
Family Coverage and Illustrations:
Hamamelidaceae
Moraceae
Fagaceae
Betulaceae
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