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23 votes
Accepted

Explaining "paraphyly" for the layperson?

These are terms to describe names we give things that don't really follow phylogeny accurately. Fish, for example - a monophyletic group involving fish would include humans, too, yet there are many ...
Bryan Krause's user avatar
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14 votes

Explaining "paraphyly" for the layperson?

One very simple example that most people are familiar with is the vernacular use of "animal". Most people recognize that humans are animals and more closely related to other animals than ...
WaterMolecule's user avatar
6 votes

Explaining "paraphyly" for the layperson?

I put some comments further up, but if I was teaching this, my first attempt would be to "acknowledge the absurdity" - basically, that these groups clearly don't, according to the genetics, ...
lupe's user avatar
  • 203
5 votes

Explaining "paraphyly" for the layperson?

To answer your specific questions But why not just make the blue area a full blue triangle to make the prosimii and simiiformes one triangle/group? In the end, we all share the same ancestor, so I ...
John's user avatar
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4 votes

Did radial symmetry evolve twice?

Good question! I had never really though about it, so thank you! Echinodermata have a pentaradial symmetry Echinodermata actually don't have a radial symmetry like jellyfish do. They have a ...
Remi.b's user avatar
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3 votes

Which synamorphy evolved last

A cladogram does not indicate time. That would be a calibrated phylogram. We can tell from the above cladogram that the two synapomorphies "Hair" and "Eggs" with shells are the two most recent, and ...
Karl Kjer's user avatar
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2 votes

Cladistics question - species of non-terminal nodes

First: tips are best thought of as individuals, not species. One might have multiple members of the same species even in a phylogeny. Recall that species / subspecies are fundamentally arbitrary ...
Maximilian Press's user avatar
2 votes
Accepted

What is the minimum number of clades necessary to partition Vertebrates while maintaining the classical groups of Birds, Mammals, and Amphibians?

Phylogenetic taxonomy of the Vertebrates (mun.ca) has the following graphic (14 clades total, minimum of 12 collapsing Amphibia): Here, what was preivously 'Fish' (the paraphyletic group of non-...
brazofuerte's user avatar
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2 votes
Accepted

Why swordfish aren't put in the same family as Marlins?

Why Swordfish (Xiphias gladius), which are very similar to Marlins, do not belong to the same family as Marlin - Istiophoridae? The decision about what we call an order vs a family is very subjective....
Remi.b's user avatar
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2 votes

If dinosaurs could have feathers, would they still be reptiles?

There have been some good answers here, but I think some information could be added. Willi Hennig introduced modern phylogenetic systematics, which is sometimes conflicting with traditional taxonomy. ...
HarvyD's user avatar
  • 21
2 votes

How are ray finned and lobe finned fish are sister clades?

The misunderstanding here is the difference between phylogenetic classification and character evolution. Essentially, just because an organism has one certain trait it doesn't automatically belong to ...
Darlingtonia's user avatar
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2 votes
Accepted

Why aren't mammals and reptiles considered amphibians?

Mammals and reptiles aren't considered amphibians, because amniotes are not hypothesized to descend from Amphibia. That is to say that Amphibia did not evolve into Amniota. They are sister clades (...
kmm's user avatar
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2 votes

Why aren't mammals and reptiles considered amphibians?

Some named groups are not monophyletic (see this post for definition if needed). Fishes do not represent a monophyletic group. Groups like "fishes" are completely awful to define but everyone would ...
Remi.b's user avatar
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2 votes
Accepted

The phylogenetic definition of the clade Dinosauria

As of right now it is still the same, the evidence for sauropodomorpha being a outgroup is not statistically more reliable, this may change, however this will still not have much impact. There are ...
John's user avatar
  • 14.7k
1 vote

The parts of the phylogenetic nomenclature that need to be "unique"

Many of the problems you are discovering are the basis for phylogenetic classification. Without necessarily answering each of your question specifically, I'll mention some of the basics of ...
kmm's user avatar
  • 12.3k
1 vote

The parts of the phylogenetic nomenclature that need to be "unique"

Binomial nomenclature does not uniquely define a species unfortunately, there are several duplicates. The Wikispecies directory shows 5 duplicates: each of this is with an organism from kingdom ...
Bryan Krause's user avatar
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1 vote

How would I represent this on a cladogram?

The short answer is that cladograms are not compatible with Linnean taxonomy. The longer answer explain how and why. First, there aren't enough ranks in Linnean taxonomy to cover all the cladogram ...
Triceratops's user avatar
  • 1,176
1 vote

Forming a cladogram from a table of information

I think the clue is at each step to look for the trait that is shared by most of the remaining taxa. In your example: 9 out of 10 taxa are vertebrae. So you are correct to pick this trait first and ...
Arsak's user avatar
  • 715
1 vote

Did radial symmetry evolve twice?

It is actually hypothesized that radial symmetry did evolve again, but there are homologies between the echinoderm symmetry and bilateral animals: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2176165/...
Chris's user avatar
  • 11
1 vote

How to read cladograms/phylograms?

-Bacteria 1 is least related to Eukaryote 4 (the furthest branch is always the least related as there common node is furthest away, correct?) In terms of relative relationships, eukaryote 4's least-...
C_Z_'s user avatar
  • 2,485

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