Comparative Cytology and the Evolution of Life

Dillon, Lawrence S.

doi:10.2307/2406270

Cited by 15 publications

(1 citation statement)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same rationale explains the greater subdivision of the "yellow brown" algae in the Leedale scheme. The endosymbiotic hypothesis has received considerable attention recently (reviews by Sagan, 1967;Margulis, 1970;Taylor, 1974) compared to the classical hypothesis which is supported by Dillon (1962), Allsopp (1969), Klein and Cronquist (1967), Jeffrey (1971), and Uzzell and Spolsky (1974). According to the latter authors "if acceptance in recent scientific literature is a measure of validity, the endosymbiosis hypothesis appears to be almost unchallengeable"; however they present several serious drawbacks to the endosymbiosis hypothesis which should stimulate more bipartite discourse.…”

mentioning

confidence: 99%

A Classification of Plants Into Higher Taxa Based on Cytological and Biochemical Criteria

Edwards

1976

TAXON

View full text Add to dashboard Cite

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. International Association for Plant Taxonomy (IAPT) is collaborating with JSTOR to digitize, preserve and extend access to Taxon. Summary A variety of schemes are employed currently for the classification of plants into higher taxa. The two most widely used schemes, the traditional kingdom Plantae with subkingdoms Thallophyta and Embryophyta, and the Whittaker five-kingdom system with plants in the kingdoms Monera, Protista, Fungi and Plantae, rely on nineteenth century morphological criteria for delimitation of taxa that result in polyphyletic assemblages of organisms. It is proposed that plants be assigned to seven kingdoms, subordinate to the superkingdoms Procaryota and Eucaryota which are based on the procaryotic and eucaryotic types of cellular organization. The distribution of accessory chlorophylls is used as a major taxonomic criterion for classifying photosynthetic organisms at the kingdom level. This results in a single kingdom, the Cyanochlorobionta for photosynthetic plants containing chlorophyll a only within the superkingdom Procaryota. Photosynthetic plants within the superkingdom Eucaryota have been divided into three groups, the kingdom Erythrobionta for organisms with no accessory chlorophyll or occasionally chlorophyll d (and lacking flagella), the kingdom Chlorobionta for organisms with accessory chlorophyll b, and the Ochrobionta for those organisms with accessory chlorophyll c. Vascular plants have been assigned to a single division, the Tracheophyta, since in addition to having a similar biochemistry (chlorophylls a and b, similar carotenoids, starch as a reserve food product) they possess also a basic morphological groundplana vascular system containing xylem and phloem, and a life history consisting of an alternation of generations. The fungi have been assigned three kingdoms as opposed to most extant schemes of classification in which they are allocated to a single polyphyletic assemblage. The true fungi have been divided into kingdoms Fungi I and Fungi 2 since it is thought that they have evolved from the Chlorobionta and Ochrobionta, respectively; the myxomycetes have been placed in a third kingdom, the Myxobionta.A perusal of eighteen botanical books published in the U.S.A. during the last decade has revealed a considerable lack of uniformity in the usage of the higher categories of classification: five used the traditional two kingdom system of organisms with the kingdom Plantae for plants and the subkingdoms Thallophyta and Embryophyta; three employed the recently proposed five kingdom organismic system of Whittaker (1969) with plants in the kingdoms Monera, Protista, Plantae and Fungi; six began their treatment at the division level, presumably du...

show abstract

mentioning

confidence: 99%