Cladistic Analysis Of Trichocereus (Cactaceae: Cactoideae:
Trichocereeae) Based On Morphological DATA And Chloroplast
Dna Sequences
Sof ía Albesiano
I wanted to address and discuss this paper.
It is based on chloroplast sequences and morphological data.
Here is one of its vital flaws, if you cross two different species in this group, like pachaoi and bridgesii, the chloroplasts are going to be inherited by the seeds from the mother plant that bears them. This thows the data off.
T bridgesii is listed in the paper as having a chloroplast DNA sequence that appears ancestral to the clade, but because of the inheritance patterns this result can be questioned strongly.
if I use pachanoi pollen on a bridgesii, then the offspring will have the chloroplast DNA of the bridgesii, the reverse cross has the DNA of the pachanoi. Because of the way the plants in this genera can cross, we need chromosomal DNA analysis combined with chloroplast DNA sequences to generate useful data. The authors do not appear to aknowledge that these plants can cross and when their ranges overlap they do, interspecific hybrids are known to occur in the wild in this genera!!
Evidently bridgesii was such an issue with regard to this that the authors included it in figures 1 and 2, but omitted it from figure 3. Figure 1 is a chart made from morphological data (I consider this a joke), figure 2 is another chart made from the chloroplast DNA sequences (again deeply flawed due to inheritance patterns and cross compatability) however figure 3 is a hybrid made from the two previous figures and data. In figure 1 bridgesii is associated with pachanoi and peruvianus, in figure 2 it is ancestral to the entire clade! in figure 3 it is missing entirely.
There are many issues with this paper and I consider it totally inconclusive and even potentially misleading. The paper even includes two synonyms of the same species as distinct, see if you can spot them. They are morphologically distinct and due to inheritance patternd could have distinct DNA sequences for chloroplasts, but that does not mean they are distinct species.
There are other issues with the paper concerning method, collection and location data etc.
http://www.cactusconservation.org/CCI/library/pdf/Albesiano_Terrazas_2012_Haseltonia_17_3-23.pdf
Cladistic Analysis Of Trichocereus (Cactaceae: Cactoideae:
Trichocereeae) Based On Morphological DATA And Chloroplast
Dna Sequences
Sof ía Albesiano
I wanted to address and discuss this paper.
It is based on chloroplast sequences and morphological data.
Here is one of its vital flaws, if you cross two different species in this group, like pachaoi and bridgesii, the chloroplasts are going to be inherited by the seeds from the mother plant that bears them. This thows the data off.
T bridgesii is listed in the paper as having a chloroplast DNA sequence that appears ancestral to the clade, but because of the inheritance patterns this result can be questioned strongly.
if I use pachanoi pollen on a bridgesii, then the offspring will have the chloroplast DNA of the bridgesii, the reverse cross has the DNA of the pachanoi. Because of the way the plants in this genera can cross, we need chromosomal DNA analysis combined with chloroplast DNA sequences to generate useful data. The authors do not appear to aknowledge that these plants can cross and when their ranges overlap they do, interspecific hybrids are known to occur in the wild in this genera!!
Evidently bridgesii was such an issue with regard to this that the authors included it in figures 1 and 2, but omitted it from figure 3. Figure 1 is a chart made from morphological data (I consider this a joke), figure 2 is another chart made from the chloroplast DNA sequences (again deeply flawed due to inheritance patterns and cross compatability) however figure 3 is a hybrid made from the two previous figures and data. In figure 1 bridgesii is associated with pachanoi and peruvianus, in figure 2 it is ancestral to the entire clade! in figure 3 it is missing entirely.
There are many issues with this paper and I consider it totally inconclusive and even potentially misleading. The paper even includes two synonyms of the same species as distinct, see if you can spot them. They are morphologically distinct and due to inheritance patternd could have distinct DNA sequences for chloroplasts, but that does not mean they are distinct species.
There are other issues with the paper concerning method, collection and location data etc.
I find it to be a joke.
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