Comments on: Did Dinosaurs Roar?

By: Don Druid

Don Druid — Sun, 09 Sep 2012 11:45:58 +0000

Stephen Holland,

There is plenty of literature debating the possibility of lambeosaurines using their crests to produce sound, going back to 1931. It’s one of the most well-known debates in the field. See for instance:

Wiman, Carl (1931). “Parasaurolophus tubicen, n. sp. aus der Kreide in New Mexico” (in German). Nova Acta Regia Societas Scientarum Upsaliensis, series 4 7 (5): 1–11.

Hopson, James A. (1975). “The evolution of cranial display structures in hadrosaurian dinosaurs”. Paleobiology 1 (1): 21–43.

Weishampel, David B. (1981). “Acoustic analyses of potential vocalization in lambeosaurine dinosaurs (Reptilia:Ornithischia)”. Paleobiology 7 (2): 252–261.

Diegert, Carl F.; and Williamson, Thomas E. (1998). “A digital acoustic model of the lambeosaurine hadrosaur Parasaurolophus tubicen”. Journal of Vertebrate Paleontology 18 (3, Suppl.): 38A.

By: Stephen Holland

Stephen Holland — Fri, 27 Jul 2012 16:49:51 +0000

As a retired physics teacher and ham radio operator (VE7SVR), I am amazed at the lack of recognition of head shapes for infrasound production.
(1) Tube like structures on the head (search “Parasaurolophus” and “lambeosaurines”) to me are obvious resonant chambers, probably to tune the sounds from the throat or create their own sounds with muscles, with certain harmonics for different individuals and species, and probably tuning mechanisms.
(2) A different feature would be the wide flat fins on the head (search “ceratopsian”), with a ring of bone, which are perfectly designed as drums. As muscle controlled diaphragms, they can create sound different from the throat mechanism, but with nerve endings they can also resonate as muscle-tuned receivers. The triceratops skull has no ring, but is concave and with an outer upturned rim which has what look like muscle attachment points. I suggest it had a drum skin floating above the bony frill.

Where in the science literature is this studied? I come up with almost nothing in my searches.
Of course, such features could be used for other purposes, perhaps bone tubes for butting, and fin-drums for colorful displays.

By: Babbletrish

Babbletrish — Thu, 22 Mar 2012 19:20:14 +0000

Very unscientific counterargument: Vuvuzelas. Seems you just need wind going through a long tube to roar, so there’s that.

By: Neal W. Welsh, ret., zoologist

Neal W. Welsh, ret., zoologist — Fri, 17 Jul 2009 03:27:14 +0000

Given that birds are very probably, some paleozoologists say surely, descendants of at least one branch of dinosaurians; and that all birds we know have vocal capabilities courtesy of their syrinxes; that many birds have very sophisticated syrinxes and are producers of an extremely wide array of calls, alarms and songs, it is inconceivable that many dinosaurians would not have an array of sounds themselves. Maybe these didn’t approach the complexity of modern birds but surely there must have been a respectable range of vocalizations among many genera.

(edited for a letter omission) N.W.W.

By: JAG

JAG — Wed, 15 Jul 2009 21:37:06 +0000

All that is needed is a tube long enough, breath and some musculature coordinated enough to create intonations. I attended a Vertebrate paleontology session a few years back and one individual demonstrated a long smooth “bore” tube that he was able to get some sounds to produce. I suggested he try a corrugated tube, like those available for drainage systems (more resembling the trachea of many animals including birds). This corrugated tube could provide more eddy-producing surfaces that would encourage greater intonation. Constricting the tube diameter and length would produce greater ranges of sounds like valves on a trumpet, not only providing basic “naturals” but “sharps” and “flats”, broadening the intonation range of a vocal tube. Relaxing and tightening the tube could allow more fluttering sounds, like roars growls and such. The main issue would be the interface between “brain” and vocalizing organs. Birds do it. Why not? Imagine the vocal resonances of an Apatasaurus’s or Diplodocus’s trachea.

By: Tor Bertin

Tor Bertin — Mon, 13 Jul 2009 17:38:47 +0000

I’d actually be very surprised if some sort of vocalization structure didn’t evolve in dinosaurs as well–it just seems far too useful of an evolutionary adaptation to do without for so many millions of years.

By: Michael Stearns

Michael Stearns — Mon, 13 Jul 2009 15:49:04 +0000

Can’t vocalize eh? Just like a little so-called DINOSAURS IN SPACE?! Clearly support for Dinosaurs in Space is greater than ever!