Talk:Lancelet

It seems to me that these critters have endostyles that eventually give rise to the mammalian thyroid gland. Shouldn't this be mentioned somewhere in the lead article?

Do lancelets have eyes? If no, when did they start evolving in chordates (probably in platyhelminthes I guess)?PhoenixSeraph 22:13, 1 April 2006 (UTC)

• They have only one pigment spot on their front end which detects light.

hey, people help me translate description for image. -PioM22:55, 14 Jun 2005 (UTC)

I just added a bit about eyes. I actually have quite a bit more material, but think maybe the Physical features section should be broken down into subsections. The frontal eye alone is worth a solid paragraph. For example, it expresses the PAX6 gene, and is thought to be homologous with vertebrate paired eyes. The pigment cup has been proposed as a homologue of the RPE (Retinal pigment epithelium). The row-1 photoreceptors carry C-opsin 1, except for a few which carry C-opsin 3. They have a Gi-mediated phototransduction cascade and are thought to be homologous with vertebrate rods and cones. The first row of interneurons are seratonogenic. In the last row, the neurons on the left-hand side feed into the left ventrolateral nerve while the axons on the right side of the eye (back row) feed into the right ventrolateral nerve. The Joseph cells and Hesse organs, meanwhile have melanopsin on microvilli. Zyxwv99 (talk) 02:14, 1 December 2015 (UTC)

Commercial use

In Asia, they are harvested commercially. -- what for? Food? If so, what sort of food? --Spudtater 00:31, 21 February 2006 (UTC)

Yes, for food. Both for humans and animals. I wonder how it tastes. Would like to try it made in the same way as fish and chips.

"Today, amphioxus may be extremely common in shallow sandy environments: at Discovery Bay, Jamaica, up to five thousand individuals per square meter of sand have been reported. In some parts of the world, amphioxus are eaten by humans or by domestic animals; they are important food items in some parts of Asia, where they are commercially harvested."

From American Scientist :

"Lancelets in a bay near Xiamen, China, evidently supported a fishery for at least a few hundred years. The muscular animals were either eaten fresh (they taste like herring) or were dehydrated by roasting in a little oil and used as an additive for other dishes."

If they taste like herring, they doesn't taste bad at all. 193.217.193.154 17:54, 15 July 2007 (UTC)

Humans ?

Look at this :

"In common with the vertebrates, lancelets have a nerve cord running along the back, pharyngeal gill slits and a tail that runs past the anus. Also like humans, the muscles are arranged in blocks called myomeres. Unlike the invertebrates, however, ..."

Why "humans" ? Only humans and lancelets do have myomeres, really ?
What about other vertebrates between them ?

They are trying to emphasize that humans came from Lancelets. And they did. <--rookie error, humans did not come from lancelets. However the common ancestor of humans and lancelets would have been similar to modern day lancelets. Modern lancelets would still have evolved somewhat from this ancestor, but have retained many of the primitive features (hence they are interesting).

Subphylum relationships within the Chordata

The major "textbook view" of Chordate subphylum relationships places the lancelets as a sister-group to the vertebrates. This is the picture presented in cladograms by both Brusca & Brusca (Invertebrates, Sinauer Associates 2003) and Miller & Harley (Zoology, McGraw-Hill 2007), as well as the Three of life project. This wikipedia article, however, appears very biased in expressing the other view, which is placing Urochordates as a basal group.

Stating neutrality as a goal, wikipedia articles should try not to take stands in ongoing debates. I have seen the "newer research suggests that" argument used in advocacy of both of the vertebrate sistergroup views; it is thus not very convincing unless one also states what kind of evidence there is for either view.--Gunnar Mikalsen Kvifte (talk) 06:58, 20 December 2007 (UTC)

The accepted view today is that urochordates are closer to vertebrates and lancelets farer away. This is supported by papers in the most prestigious journals. See Blair and Hedges 2005, Delsuc et al 2006, Vienne and Pontarotti 2006 and Bourlat et al 2006 --Maximilianh (talk) 22:34, 9 May 2009 (UTC)

I agree with the last user (Maximilianh): The issue has been settled, as evidenced by a string of high-profile studies relying on modern methods of phylogenetics. See also the wikipedia article on Chordates and references [46][47][48][49]. The statement that lancelets are the closest living invertebrate relatives of vertebrates is wrong and should be corrected. In particular the figure caption presents the old and superseded view as a fact: "The lancelet is a small, translucent, fish-like animal that is the closest living invertebrate relative of the vertebrates.[33][34]" — Preceding unsigned comment added by 134.76.223.13 (talk) 15:35, 8 December 2018 (UTC)

Images

You can use this ( ) excellent image for your article ^___^. Also you can translate the article about amphioxus from Russian Wikipedia --LameClock (talk) 11:18, 4 June 2008 (UTC)

How big it is? Could some one provide the detailed average dimensions (metric units please) of an adult lancelet? —Preceding unsigned comment added by 128.163.42.93 (talk) 22:31, 9 January 2009 (UTC)

The anatomical drawing of the lancet labels the finger-like projections near the mouth as ″13. mimosa″ Is that correct? I can't find that usage of mimosa anywhere else on Wikipedia or the web (though it may just be difficult to find on the web due to other more common uses). — Preceding unsigned comment added by 129.55.200.20 (talk) 15:27, 28 May 2013 (UTC)

Asymmetric Nature of Juveniles

What symmetry are juveniles missing? Anatomic symmetry, meaning they're not bilaterally symmetric as the adults are? Kanenas (talk) 20:43, 26 July 2008 (UTC)

Valid species

I did a search on Google Scholar for each of the species listed here, filtering for hits since the year 2000. The number to the left of each item indicate how many hits it got. As a measure of scientific and taxonomic validity, this is obviously WP:OR. On the other hand, it is a replicable measure of notability (WP:NOTABLE).

17 Asymmetron inferum 78 Asymmetron lucayanum 1 Epigonichthys australis 0 Epigonichthys bassanus 0 Epigonichthys cingalensis 7 Epigonichthys cultellus 5 Epigonichthys hectori 29 Epigonichthys maldivensis 0 Branchiostoma africae 0 Branchiostoma arabiae 0 Branchiostoma bazarutense 2420 Branchiostoma belcheri 2 Branchiostoma bennetti 1 Branchiostoma bermudae 38 Branchiostoma californiense 0 Branchiostoma capense 68 Branchiostoma caribaeum 0 Branchiostoma clonaseum 20 Branchiostoma elongatum 3510 Branchiostoma floridae 0 Branchiostoma gambiense 7 Branchiostoma indicum 207 Branchiostoma japonicum 1350 Branchiostoma lanceolatum 0 Branchiostoma leonense 1 Branchiostoma longirostrum 10 Branchiostoma malayanum 0 Branchiostoma moretonense 39 Branchiostoma nigeriense 43 Branchiostoma platae 16 Branchiostoma senegalense 0 Branchiostoma tattersalli 33 Branchiostoma virginiae

Zyxwv99 (talk) 02:19, 15 December 2015 (UTC)

Added section on fluorescent proteins and updated the anatomical diagram

Lancelets produce GFP. I added an updated diagram based off of recent literature (2017).
(Single Eukaryote | talk | 22:16, 13 January 2021 (UTC))

missing references

the following citations occur in #Habitat and these need to be added as references: Webb and Hill, 1958; Webb, 1958; Boschung and Gunter, 1962; Cory and Pierce, 1967; Gosselck and Spittler, 1979; Caccavale et al., 2021b; Desdevises et al., 2011 Stokes and Holland, 1996a; Stokes, 1996 Zhang et al., 2001 Marci68 (talk) 20:23, 4 August 2024 (UTC)

Years given at splits in cladogram far too recent

I think this very good article lets itself down a bit in the end, where dates for major splits between spits in the phylum Chordata shown are clearly far to recent. As there are well accepted different chordate-lineages as fish (Haikouichthys) and tunicates (Shankouclava) found 518 million years ago, the split between craniates and tunicates must have happened way before that, I would suggest at least 60 million years needed to get such major differences in bodyplans (so > 580 mya). If the Ediacaran fossil Burykhia hunti is indeed a tunicate, for which the article from Fedonkin makes a very pursuasive case, than we are in the > 615 mya regions. The split between Cephalochordates and Olifactares was even earlier. That is also consistent with many genomic articles on basic timelines of major splits. Codiv (talk) 14:34, 20 August 2024 (UTC)

Whatever you find "convincing" is irrelevant. I I'm not particularly attached to the numbers, but I think they represent effectively minimum split ages rather than true divergence ages I would suggest at least 60 million years needed to get such major differences in bodyplans is just baseless personal speculation. We base article content on what sources say, not our personal opinions. Hemiauchenia (talk) 20:23, 20 August 2024 (UTC)