en.wikipedia.org/wiki/Colossal_squid
2 corrections found
located next to the lens on the front of both eyeballs.
This misstates where the colossal squid’s eye photophores are. Te Papa and review literature place them on the rear/ventral side of each eyeball, not on the front.
Full reasoning
Official descriptions of the colossal squid’s eye photophores do not place them on the front of the eye.
- Te Papa’s anatomy page says: “Each light organ is a vertical band on the rear of the eyeball, beside the outer edge of the lens.”
- Te Papa’s research blog likewise says the specimen has “photophores at the rear of each eyeball” and that the ocular photophore is “located at the rear of the eye.”
- A review of Mesonychoteuthis hamiltoni describes the photophores as “two elongate structures on the ventral surface of each eye,” with one anterior and the larger one posterior around the iris.
So the article’s wording incorrectly relocates the photophores to the front of the eyeballs.
3 sources
- The eyes of the colossal squid | Te Papa
“Each light organ is a vertical band on the rear of the eyeball, beside the outer edge of the lens.”
- Here's looking at you (in the dark) | Te Papa's Blog
“The colossal squid specimen has photophores at the rear of each eyeball … The ocular photophore of the colossal squid however, is located at the rear of the eye.”
- Biology and ecology of the world's largest invertebrate, the colossal squid (Mesonychoteuthis hamiltoni): a short review
The review states that M. hamiltoni possesses photophores “in the form of two elongate structures on the ventral surface of each eye,” with the smaller located anteriorly and the larger posteriorly around the iris.
which is the upper limit of the sperm whale's sonar range.
This reverses the underlying source. The paper on squid eye size says sperm whale sonar range exceeds 120 m, so 120 m is not the upper limit.
Full reasoning
The article appears to have inverted the result of the source it is drawing from.
Nilsson et al. (2012), the well-known paper on giant/colossal squid eye size, says giant squid eyes could detect sperm whales at distances exceeding 120 m and then explicitly adds: “Because the sonar range of sperm whales exceeds 120 m…” In other words, the paper says sperm whale sonar reaches beyond 120 m, not that 120 m is its upper limit.
Later direct measurements are consistent with that wording. Tønnesen et al. (2020) reported that a tagged sperm whale detected organisms up to 144 m ahead of the whale, supporting a long-range echolocation function.
So the sentence in the article is incorrect because it states the opposite of the cited literature.
2 sources
- A unique advantage for giant eyes in giant squid | Scholars@Duke / Current Biology
The abstract says squid eyes could allow detection of sperm whales “at distances exceeding 120 m” and adds: “Because the sonar range of sperm whales exceeds 120 m [3-5]…”
- The long-range echo scene of the sperm whale biosonar - PubMed
The abstract reports “over 6000 echo streams from organisms detected up to 144 m ahead of the whale,” supporting “a long-range prey detection function of the sperm whale biosonar.”