# Talk:Sea urchin

The lead lists sea otters, wolf eels and triggerfish as Main predators Of sea urchin. I’m pretty sure this was sourced from somewhere talking only about sea urchins in the northeast pacific probably California. Since this is the article on urchins as a whole not just the those on the west coast of North America I’m going to loosen the language a bit 75.142.22.164 (talk) 19:44, 18 August 2022 (UTC)

characteristic 103.167.233.7 (talk) 01:34, 1 December 2022 (UTC)

The first paragraph is very chatty and not well written
> Sea urchins might appear to be incapable of moving but this is a false impression. [Really? you're assuming a lot about what I think]  In some cases, [which cases specifically are you talking about and which are you not?] the most visible sign of life is the spines, which are attached to ball-and-socket joints [they are NOT ball and socket joints] and can point in any direction; in most urchins, touch elicits a prompt reaction from the spines, which converge toward the touched point. [this is NOT related to them moving, but is more a defence mechanism - so put it in a different paragraph.] Sea urchins have no visible eyes, legs, or means of propulsion, [chatty, do they have invisible eyes?] but can move freely but slowly over hard surfaces using adhesive tube feet, working in conjunction with the spines. [is this not a means of propulsion?]

Some of the spines are 6 inches long. Do you mean to say that the tube-feet can extend that long to reach past the spines and move the urchin? Lehasa (talk) 15:40, 28 December 2022 (UTC)

I've fixed it up now.
Various resources I've found are listed below. Perhaps they'll be useful for anyone who wants to improve things more.
http://www.chalk.discoveringfossils.co.uk/CIDAROID_terminology.htm
https://ns-echinodermata.linnaeus.naturalis.nl/linnaeus_ng/app/views/introduction/topic.php?id=2845
https://cronodon.com/BioTech/echinoids.html
http://animaldiversity.org/site/accounts/information/Echinoidea.html
https://www.nhm.ac.uk/our-science/data/echinoid-directory/morphology/regulars/intro.html Lehasa (talk) 20:23, 28 December 2022 (UTC)

Reproduction only talks about male sea urchins. What about females? It does say there are clear male female sea urchins. Cowcatmom (talk) 17:13, 21 August 2023 (UTC)

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A temporary editor is attempting to insist that a single short example has to be separated by commas. The sentence however reads just fine in plain (British) English without additional punctuation-clutter. In addition, it's no good trying to force a change into an article by edit-warring: things must stay as they are until consensus is reached. Chiswick Chap (talk) 08:14, 20 November 2025 (UTC)