Development of classification Flashcards

Question

Michel Adanson

Answer 1

arranged plants into groups similar to our orders and families -Familles des Plantes

Answer 2

Adanson emphasized that many characters should be used in a classification scheme, and that equal weight should be placed on each unless detailed studies showed that some were more important taxonomically. This is called the empirical approach

Answer 3

Antoine, Bernard, Joseph, Antoine-Laurent (major step towards natural plant families)

Answer 4

Acotyledones (cryptogams and a few misplaced monocots) • Monocotyledones (monocots) • Dicotyledones (dicots and gymnosperms).

Answer 5

``` Augustin Pyramus De Candolle, Alphonse -They divided plants into two major groups: • Cellulares (nonvascular) • Vasculares (vascular) -began dicots with Ranunculaceae ```

Answer 6

Genera Plantarum -The dicots were divided into three groups: • Polypetalae (free petals) • Gamopetalae (fused petals) • Monochlamydeae (apetalous) -species concepts were based on the idea that species are fixed entities, unchanged through time and placed on the earth by the Creator. British herbaria, such as Kew and the British Museum, are still arranged according to the Bentham and Hooker system (pre darwin)

Answer 7

Darwin's Origin of Species (1859) did much to alter the basic concepts used in determining relationships. Attempts to follow his principles resulted in systems that arranged natural groups in a phylogenetic (evolutionary) sequence progressing from the simplest (most primitive) to the more complex (most advanced).

Answer 8

based his system on morphological information -For example, his system divided the non-seed plants into the: • Thallophyta (liverworts) • Bryophyta (mosses) • Pteridophyta (ferns and allies)

Answer 9

Adolph Engler (1844-1930) and Karl Prantl (1849- 1893), and is referred to as the Englerian School.

Answer 10

-now considered incorrect (equated “simple” with “primitive) Monocots preceded the dicots in this system, and dicots were divided into the: • Archichlamydeae (free petals or no petals) • Metachlamydeae (fused petals) -Engler considered plants with simple, unisexual flowers to be primitive. The first group of dicots were the Amentiferae (wind- pollinated, catkin-bearing plants and their relatives). Modern families with these traits are Betulaceae, Fagaceae, and Juglandaceae.

Answer 11

Outlines of Plant Phylaflowering plants began with the Magnoliaceae- Ranunculaceae complex. -This complex was comprised of primarily insect-pollinated plants. This group gave rise to the other dicots and to the monocots. He considered the wind pollinated Amentiferous families to be secondarily reduced.

Answer 12

Bessey’s system, which was really a modified Bentham and Hooker classification, was based on a set of dicta or concepts of primitive features found in ancient plants versus the advanced characters of more recently evolved plants.

Answer 13

woody preceded herbs, vines, and climbers • perennials preceded biennials and annuals • vascular bundles in a ring (dicots) preceded vascular bundles scattered (monocots) • alternate leaves preceded opposite or whorled leaves • simple leaves preceded compound leaves • bisexual flowers preceded unisexual flowers -many-parted flowers preceded few-parted flowers • actinomorphic (regular) flowers preceded zygomorphic (irregular) flowers • separate perianth parts preceded fused perianth parts • flowers with petals usually preceded apetalous ones • many separate stamens preceded few or united stamens -hypogyny (superior ovary) preceded epigyny (inferior ovary) • generally, numerous separate carpels preceded fewer, fused carpels • pollen grains with one pore preceded those with three pores • axile placentation preceded free central placentation • simple fruits preceded aggregate fruits

Answer 14

attempted to show the interrationships among the various orders he recognized.

Answer 15

The Families of Flowering Plants provided ready keys and descriptions to the families. -

Answer 16

Monocotyledones (monocots) • Herbaceae Dicotyledones (herbaceous dicots) • Lignosae Dicotyledones (woody dicots) -He suggested that monocots were derived from certain primitive herbaceous dicots (Ranales), and all other herbaceous dicots were also derived from the Ranales -The woody dicots were said to be derived from the Magnoliales -major flaw was this division of the dicots into a woody versus herbaceous lines -but excellent family descriptions

Answer 17

Takhtajan, cronquist, Thorne, and dalgren

Answer 18

Takhtajan described the earliest angiosperms as follows: • small woody plants • leaves simple, entire, and pinnately veined • flowers solitary, of moderate size, arrangement terminal and axillary -flowers actinomorphic, bisexual • numerous sepals, petals, stamens, and carpels • stamens leaflike, pollen monosulcate • carpels unsealed, conduplicate with the stigmatic surface along the margin These would have been similar to members of the present-day Magnoliaceae. Magnoliales was the most primitive group of flowering plants, and all others evolved from it. He believed that the monocots evolved from a precursor of the order Nymphaeales recognized the classes Magnoliopsida and Liliopsida in the Phylum Magnoliophyta

Answer 19

agreed with Takhtajan but Cronquist recognized 11 subclasses (instead of 10) -Cronquist included Takhtajan's Ranunculidae in his own Magnoliidae. In addition, he divided Takhtajan's Liliidae into his Liliidae, Commelinidae, and Zingiberidae.

Answer 20

57 orders and 395 families in the two subclasses Dicotyledoneae and Monocotyledoneae - 'phylogenetic shrub'

Answer 21

``` placed all of the angiosperms in Class Magnoliopsida -He did not recognize subclasses in the same sense that Cronquist and Takhtajan did, although he did distinguish between the dicots (subclass Magnoliidae) and monocots (subclass Liliidae) as distinct groups ```

Answer 22

Amentiferae