My friend Toby Lowther wrote to me back in December to ask this question: It’s strange, isn’t it? The last I knew, Shonisaurus was the largest ichthyosaur, at about 20 m and 50 tonnes, and this is considerably bigger than any plesiosaur or mosasaur I know of. It’s up the sperm-whale size category, but not even close to the bigger baleen whales. Why not?

This recent news story tells of a cane toad found in Australia that weighs six pounds.

I have long intended to write a paper entitled Why Elephants Are So Small, as a companion piece to Why Giraffes Have Short Necks (Taylor and Wedel 2013). I’ve often discussed this project with Matt, usually under the acronym WEASS, and its substance has come up in the previous post, and especially Mickey Mortimer’s comment: That is exactly what the WEASS project was supposed to consist of: a list of many candidate limitations on how big animals

Consider a small sauropod of length x , as shown on the left above. Its mass is proportional to x cubed, it stands on leg bones whose cross-sectional area is x squared, and it ingests food through a gullet whose cross-sectional area is x squared. Now consider a larger sauropod of length 2 x , as shown on the right above.

In a comment on the last post, Mike wrote, “perhaps the pneumaticity was intially a size-related feature that merely failed to get unevolved when rebbachisaurs became smaller”. {.wp-image-6447 .size-large aria-describedby=“caption-attachment-6447” loading=“lazy” attachment-id=“6447” permalink=“http://svpow.com/2012/06/28/hot-sauropod-news-part-1-rampant-pneumaticity-in-saltasaurines/caudal-pneumaticity-in-saltasaurines-cerda-et-al-2012-fig-1/”

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This will be all too short, but I can’t let the publication of a new giant sauropod pass unremarked.

I just gave an answer to this question on Quora, and it occurred to me that I ought to also give it a permanent home here.

I was contacted recently by David Goldenberg (dgoldenberg@gmail.com), a journalist who’s putting together a piece on the biggest dinosaurs. He asked me a few questions, and since I’d taken the time to write answers I thought I may as well post them here.

I’ve been taking a long-overdue look at some of the recently-described giant sauropods from China, trying to sort out just how big they were. Not a new pursuit for me, just one I hadn’t been back to in a while. Also, I’m not trying to debunk anything about this animal – as far as I know, there was no bunk to begin with – I’m just trying to get a handle on how big it might have been, for my own obscure purposes.