The cladistic revolution–can it make the grade?

Halstead, L. B.

doi:10.1038/276759a0

Cited by 53 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Teachers may often assume that cladograms are self-explicatory graphic devices to illustrate phylogenetic relationships, when in fact their interpretation is not trivial. As Halstead ( 1978 :760) put it: “Cladograms are difficult enough for experts in the field to comprehend fully”. Ironically, what he was advocating as the obvious alternative was phylograms—which were meant to not only express phylogenetic relationships, but, in addition, phenotypic similarity, distribution through geologic time and species number.…”

Section: Discussionmentioning

confidence: 99%

Tree thinking cannot taken for granted: challenges for teaching phylogenetics

Sandvik

2008

Theory Biosci.

View full text Add to dashboard Cite

Tree thinking is an integral part of modern evolutionary biology, and a necessary precondition for phylogenetics and comparative analyses. Tree thinking has during the 20th century largely replaced group thinking, developmental thinking and anthropocentricism in biology. Unfortunately, however, this does not imply that tree thinking can be taken for granted. The findings reported here indicate that tree thinking is very much an acquired ability which needs extensive training. I tested a sample of undergraduate and graduate students of biology by means of questionnaires. Not a single student was able to correctly interpret a simple tree drawing. Several other findings demonstrate that tree thinking is virtually absent in students unless they are explicitly taught how to read evolutionary trees. Possible causes and implications of this mental bias are discussed. It seems that biological textbooks can be an important source of confusion for students. While group and developmental thinking have disappeared from most textual representations of evolution, they have survived in the evolutionary tree drawings of many textbooks. It is quite common for students to encounter anthropocentric trees and even trees containing stem groups and paraphyla. While these biases originate from the unconscious philosophical assumptions made by authors, the findings suggest that presenting unbiased evolutionary trees in biological publications is not merely a philosophical virtue but has also clear practical implications.

show abstract

Section: Discussionmentioning

confidence: 99%

Tree thinking cannot taken for granted: challenges for teaching phylogenetics

Sandvik

2008

Theory Biosci.

View full text Add to dashboard Cite

show abstract

“…This is an early formulation of a “three‐taxon‐statement”. Compare the much publicized modern example of “the salmon, the lungfish, and the cow” (Halstead, 1978; C. Patterson, cited by Clouthier and Ahlberg, 1996, p. 445; see also Williams and Ebach, 2007) with one of Tschulok’s (1922, p. 116): doubtless, the lamprey is very different from any gnathostome, but when the chordate nature of Amphioxus was recognized, it became clear that the lamprey is nevertheless closer to gnathostome “fishes” than is Amphioxus . Note that this is not, for Tschulok (1922), a statement about phylogeny, or a phylogenetic tree; it is simply an expression of order in nature that allows the reconstruction of the “natural system”.…”

Section: Coherence Congruence and The Truth Of The “Theory Of Descent”mentioning

confidence: 99%

Sinai Tschulok (1875–1945)—a pioneer of Cladistics

Rieppel

2010

Cladistics

View full text Add to dashboard Cite

show abstract

“…As with phenetics, there is surely a hidden subjective step when characters are selected (Halstead, 1978;Hull, 1979). Cladistic analyses depend upon the definition of the primitive character state, so that changes from this state can be identified.…”

Section: Cladistic Analysismentioning

confidence: 99%

Methods of classifying nemerteans: an assessment

Moore¹,

Gibson

1993

Hydrobiologia

View full text Add to dashboard Cite

Phenetic, cladistic and phyletic methods of classifying animals are discussed with particular reference to nemerteans. It is concluded that phenetic (numerical) taxonomy is particularly inapplicable to any group of invertebrates for which well defined character differences are relatively few, whilst both the phenetic and cladistic methods fail through their fundamental assumption that convergent evolution is a rare occurrence. Terrestrial and freshwater nemerteans especially demonstrate convergent evolution in many ways; cladistic classifications proposed for these animals are therefore untenable. Convergence is shown to be a common occurrence in other nemerteans also. It is concluded that because the traditional phyletic approach does not implicitly assume that resemblances between organisms are more likely to be due to common ancestry than to convergence, it is far more likely to reveal true evolutionary relationships between taxa.

show abstract

The cladistic revolution–can it make the grade?

Cited by 53 publications

References 0 publications

Tree thinking cannot taken for granted: challenges for teaching phylogenetics

Tree thinking cannot taken for granted: challenges for teaching phylogenetics

Sinai Tschulok (1875–1945)—a pioneer of Cladistics

Methods of classifying nemerteans: an assessment

Contact Info

Product

Resources

About