Very low pressures drive ventilatory flow in chimaeroid fishes

Mason N. Dean, Adam P. Summers, Lara Ferry

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Chimaera (Holocephali) are cartilaginous fishes with flexible operculi rather than external gill slits, suggesting ventilation occurs in a manner different from other fishes. We examined holocephalan ventilation morphology, behavior, and performance by anatomical investigations, high-speed video, and in vivo pressure measurements from the buccal and parabranchial cranial cavities in Hydrolagus colliei and Callorhinchus callorynchus. Ventilatory modes ranged from quiet resting breathing to rapid "active" breathing, yet external cranial movements-excepting the passive movement of the opercular flap-were always extremely subtle, and pressures generated were one to two orders of magnitude lower than those of other fishes. To explain ventilation with such minimal pressure generation and cranial motion, we propose an "accordion" model, whereby rostrocaudal movement of the visceral arches drives pressure differentials, albeit with little lateral or ventral movement. Chimaeroids have comparatively large oropharyngeal cavities, which can move fluid with a smaller linear dimension change than the comparatively smaller cavities of other fishes. Orobranchial pressures are often less than parabranchial pressures, suggesting flow in the "wrong" direction; however, the long gill curtains of chimaeroids may passively restrict backflow. We suggest that constraints on holocephalan jaw and hyoid movements were compensated for evolutionarily by novel visceral arch mechanics and kinematics.

Original languageEnglish (US)
Pages (from-to)461-479
Number of pages19
JournalJournal of Morphology
Volume273
Issue number5
DOIs
StatePublished - May 2012

Fingerprint

Fishes
Pressure
fish
Branchial Region
Ventilation
Chondrichthyes
breathing
gills
Hydrolagus colliei
Respiration
Chimaera (Chimaeridae)
Cheek
Jaw
Mechanics
kinematics
jaws
Biomechanical Phenomena
mechanics
Drive

Keywords

  • Cartilaginous fishes
  • Chimaera
  • Gills
  • Holocephali
  • Ventilation

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Developmental Biology

Cite this

Very low pressures drive ventilatory flow in chimaeroid fishes. / Dean, Mason N.; Summers, Adam P.; Ferry, Lara.

In: Journal of Morphology, Vol. 273, No. 5, 05.2012, p. 461-479.

Research output: Contribution to journalArticle

Dean, Mason N. ; Summers, Adam P. ; Ferry, Lara. / Very low pressures drive ventilatory flow in chimaeroid fishes. In: Journal of Morphology. 2012 ; Vol. 273, No. 5. pp. 461-479.
@article{1196b3a7a0514312b42d4d6dab332da9,
title = "Very low pressures drive ventilatory flow in chimaeroid fishes",
abstract = "Chimaera (Holocephali) are cartilaginous fishes with flexible operculi rather than external gill slits, suggesting ventilation occurs in a manner different from other fishes. We examined holocephalan ventilation morphology, behavior, and performance by anatomical investigations, high-speed video, and in vivo pressure measurements from the buccal and parabranchial cranial cavities in Hydrolagus colliei and Callorhinchus callorynchus. Ventilatory modes ranged from quiet resting breathing to rapid {"}active{"} breathing, yet external cranial movements-excepting the passive movement of the opercular flap-were always extremely subtle, and pressures generated were one to two orders of magnitude lower than those of other fishes. To explain ventilation with such minimal pressure generation and cranial motion, we propose an {"}accordion{"} model, whereby rostrocaudal movement of the visceral arches drives pressure differentials, albeit with little lateral or ventral movement. Chimaeroids have comparatively large oropharyngeal cavities, which can move fluid with a smaller linear dimension change than the comparatively smaller cavities of other fishes. Orobranchial pressures are often less than parabranchial pressures, suggesting flow in the {"}wrong{"} direction; however, the long gill curtains of chimaeroids may passively restrict backflow. We suggest that constraints on holocephalan jaw and hyoid movements were compensated for evolutionarily by novel visceral arch mechanics and kinematics.",
keywords = "Cartilaginous fishes, Chimaera, Gills, Holocephali, Ventilation",
author = "Dean, {Mason N.} and Summers, {Adam P.} and Lara Ferry",
year = "2012",
month = "5",
doi = "10.1002/jmor.11035",
language = "English (US)",
volume = "273",
pages = "461--479",
journal = "Journal of Morphology",
issn = "0362-2525",
publisher = "John Wiley and Sons Inc.",
number = "5",

}

TY - JOUR

T1 - Very low pressures drive ventilatory flow in chimaeroid fishes

AU - Dean, Mason N.

AU - Summers, Adam P.

AU - Ferry, Lara

PY - 2012/5

Y1 - 2012/5

N2 - Chimaera (Holocephali) are cartilaginous fishes with flexible operculi rather than external gill slits, suggesting ventilation occurs in a manner different from other fishes. We examined holocephalan ventilation morphology, behavior, and performance by anatomical investigations, high-speed video, and in vivo pressure measurements from the buccal and parabranchial cranial cavities in Hydrolagus colliei and Callorhinchus callorynchus. Ventilatory modes ranged from quiet resting breathing to rapid "active" breathing, yet external cranial movements-excepting the passive movement of the opercular flap-were always extremely subtle, and pressures generated were one to two orders of magnitude lower than those of other fishes. To explain ventilation with such minimal pressure generation and cranial motion, we propose an "accordion" model, whereby rostrocaudal movement of the visceral arches drives pressure differentials, albeit with little lateral or ventral movement. Chimaeroids have comparatively large oropharyngeal cavities, which can move fluid with a smaller linear dimension change than the comparatively smaller cavities of other fishes. Orobranchial pressures are often less than parabranchial pressures, suggesting flow in the "wrong" direction; however, the long gill curtains of chimaeroids may passively restrict backflow. We suggest that constraints on holocephalan jaw and hyoid movements were compensated for evolutionarily by novel visceral arch mechanics and kinematics.

AB - Chimaera (Holocephali) are cartilaginous fishes with flexible operculi rather than external gill slits, suggesting ventilation occurs in a manner different from other fishes. We examined holocephalan ventilation morphology, behavior, and performance by anatomical investigations, high-speed video, and in vivo pressure measurements from the buccal and parabranchial cranial cavities in Hydrolagus colliei and Callorhinchus callorynchus. Ventilatory modes ranged from quiet resting breathing to rapid "active" breathing, yet external cranial movements-excepting the passive movement of the opercular flap-were always extremely subtle, and pressures generated were one to two orders of magnitude lower than those of other fishes. To explain ventilation with such minimal pressure generation and cranial motion, we propose an "accordion" model, whereby rostrocaudal movement of the visceral arches drives pressure differentials, albeit with little lateral or ventral movement. Chimaeroids have comparatively large oropharyngeal cavities, which can move fluid with a smaller linear dimension change than the comparatively smaller cavities of other fishes. Orobranchial pressures are often less than parabranchial pressures, suggesting flow in the "wrong" direction; however, the long gill curtains of chimaeroids may passively restrict backflow. We suggest that constraints on holocephalan jaw and hyoid movements were compensated for evolutionarily by novel visceral arch mechanics and kinematics.

KW - Cartilaginous fishes

KW - Chimaera

KW - Gills

KW - Holocephali

KW - Ventilation

UR - http://www.scopus.com/inward/record.url?scp=84858795788&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84858795788&partnerID=8YFLogxK

U2 - 10.1002/jmor.11035

DO - 10.1002/jmor.11035

M3 - Article

VL - 273

SP - 461

EP - 479

JO - Journal of Morphology

JF - Journal of Morphology

SN - 0362-2525

IS - 5

ER -