Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Osmoregulation in Fishes

Osmoregulation in Fishes

When cells are placed in a hypotonic (low-salt) fluid, they can swell and burst. Meanwhile, cells in a hypertonic solution—with a higher salt concentration—can shrivel and die. How do fish cells avoid these gruesome fates in hypotonic freshwater or hypertonic seawater environments?

Marine Microbial Ecology

Marine Microbial Ecology

Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...

Oxygen Requirements and Growth Patterns

Oxygen Requirements and Growth Patterns

Microorganisms exhibit diverse oxygen requirements and growth patterns driven by their metabolic strategies and environmental adaptations. Oxygen, while essential for many organisms, can also be toxic under certain conditions, shaping how microorganisms grow and survive.Oxygen Requirements of MicroorganismsMicroorganisms are classified based on their ability to use or tolerate oxygen:● Obligate aerobes like Mycobacterium tuberculosis need oxygen for energy production, as it serves as the...

Primary Production

Primary Production

The total amount of energy acquired by primary producers in an ecosystem is called gross primary production (GPP). However, of this energy, producers use some for metabolic processes, and some is lost as heat, decreasing the amount of energy available to the next trophic level. The remaining usable amount of energy is called the net primary productivity (NPP). In terrestrial ecosystems, NPP is driven by climate, while light penetration and nutrient availability drive NPP in aquatic ecosystems.

Sustainable Development

Sustainable Development

As the human population continues to grow and use resources, we must be mindful of our planet’s natural limits. Sustainable development provides a pathway to maintain and improve human life now while also ensuring that future generations will have the resources that they need. The long-term success of sustainability efforts rests on understanding the interplay between human actions and ecological systems.

What is an Ecosystem?

What is an Ecosystem?

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Protocol to model tumor hypoxia in vitro using real-time phosphorescence-based sensing of O<sub>2</sub> gradients generated by metastatic cancer cells.

STAR protocols·2025

Same author

Mid-Devonian ocean oxygenation enabled the expansion of animals into deeper-water habitats.

Proceedings of the National Academy of Sciences of the United States of America·2025

Same author

Human hair as a diagnostic tool in medicine.

Biochemistry and biophysics reports·2025

Same author

Repeated occurrences of marine anoxia under high atmospheric O<sub>2</sub> and icehouse conditions.

Proceedings of the National Academy of Sciences of the United States of America·2025

Same author

Sox as a Functionally Conserved Link Between Unicellular Ancestors and Human Stem Cell Control.

Cellular reprogramming·2025

Same author

Benthic diel oxygen variability and stress as potential drivers for animal diversification in the Neoproterozoic-Palaeozoic.

Nature communications·2025

Search research articles

Related Experiment Video

Updated: Jun 2, 2026

Streamlined Sampling and Cultivation of the Pelagic Cosmopolitan Larvacean, Oikopleura dioica

Streamlined Sampling and Cultivation of the Pelagic Cosmopolitan Larvacean, Oikopleura dioica

Published on: June 16, 2020

Do large predatory fish track ocean oxygenation?

Tais W Dahl¹, Emma U Hammarlund

¹Nordic Center for Earth Evolution and Institute of Biology; University of Southern Denmark; Odense C, Denmark.

Communicative & Integrative Biology

|April 22, 2011

Summary

Early fish size was limited by ocean oxygen levels. A new model suggests large predatory fish require higher oxygen concentrations, explaining why giant fish evolved only after the Devonian oxygenation event.

Keywords:

Paleozoic Placoderms fish metabolism ocean oxygenation oxygen vertebrate evolution

More Related Videos

A Strain Gauge Monitor (SGM) for Continuous Valve Gape Measurements in Bivalve Molluscs in Response to Laboratory Induced Diel-cycling Hypoxia and pH

A Strain Gauge Monitor (SGM) for Continuous Valve Gape Measurements in Bivalve Molluscs in Response to Laboratory Induced Diel-cycling Hypoxia and pH

Published on: August 1, 2018

A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

Published on: June 28, 2016

Related Experiment Videos

Last Updated: Jun 2, 2026

Streamlined Sampling and Cultivation of the Pelagic Cosmopolitan Larvacean, Oikopleura dioica

Streamlined Sampling and Cultivation of the Pelagic Cosmopolitan Larvacean, Oikopleura dioica

Published on: June 16, 2020

A Strain Gauge Monitor (SGM) for Continuous Valve Gape Measurements in Bivalve Molluscs in Response to Laboratory Induced Diel-cycling Hypoxia and pH

A Strain Gauge Monitor (SGM) for Continuous Valve Gape Measurements in Bivalve Molluscs in Response to Laboratory Induced Diel-cycling Hypoxia and pH

Published on: August 1, 2018

A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

A Simple Approach to Manipulate Dissolved Oxygen for Animal Behavior Observations

Published on: June 28, 2016

Area of Science:

Paleontology
Oceanography
Evolutionary Biology

Background:

The Devonian period saw the emergence of large armored fish (placoderms), coinciding with increased oceanic oxygen levels.
Extant large fish exhibit lower tolerance to hypoxia compared to smaller fish, suggesting size limitations related to oxygen availability.

Purpose of the Study:

To hypothesize that low Early Paleozoic oceanic oxygen levels restricted the size of marine predatory fish.
To establish a lower limit for oceanic oxygen concentrations based on the oxygen demands of large predatory fish.

Main Methods:

Comparative analysis of oxygen tolerance in extant fish of varying sizes.
Development of a simple model to assess oxygen uptake and demand relative to fish size and lifestyle.
Application of the model to estimate required oxygen levels for different predator sizes.

Main Results:

Oxygen demand and uptake scale positively with fish size.
For large, active predatory fish, oxygen demand exceeds supply at lower oxygen concentrations.
The model indicates that 2-10 meter long predators require >30-50% PAL, while smaller fish can survive at <25% PAL.

Conclusions:

Early Paleozoic oceanic oxygen levels likely limited fish to less than 1 meter in size.
The Devonian oxygenation event was a critical factor enabling the evolution of larger marine predatory fish.
Fish size evolution is strongly linked to environmental oxygen availability and physiological constraints.