natural-world-facts 2 years ago
Leo's Deep Sea Documentaries #Wildlife

The Alien World of Deep Sea Molluscs

Molluscs like cephalopods and gastropods dominate the marine world. Inhabiting nearly every ecosystem from shallow reefs to deep sea vents and the pelagic midwater, the success of molluscs is unparalleled.

Nearly 25% of all marine organisms are molluscs, including such oddities as sea snails, nudibranchs, and coleoids like squid with their specialised tentacles. Even the snails you might find in your garden belong to the molluscs, for this is the only phylum with species found in the sea, freshwater and on land.


A testament to their adaptability. With an estimated 85,000 living species known to science, the abundance and diversity of molluscs is what allows them to occupy a great many niches and habitats, and diversify into an assortment of shapes and sizes.


The smallest meiofauna molluscs grow to just 0.4 mm long, while in the pelagic deep they dominate as voracious predators, looming out of the dark. This is the alien world of molluscs.


00:00 - Introduction to Molluscs

01:50 - Anatomy of Molluscs - Basic Body Plan

02:59 - Anatomy of Molluscs - Adaptations of the Foot

04:01 - Anatomy of Molluscs - Adaptations of the Shell

04:45 - Gastropods - Anatomy and Adaptation

05:49 - Gastropods - Life in the Intertidal Zone

06:39 - Gastropods - Defence Mechanisms

07:28 - Gastropods - The Scaly-foot Snail

08:29 - Gastropods - The Nudibranchs (Sea Slugs)

09:45 - Bivalves - Anatomy and Adaptation

10:20 - Bivalves - Infaunal Lifestyle

11:26 - Bivalves - Epifaunal Lifestyle

12:09 - Bivalves - Mussel Beds of the Deep Sea

13:46 - Cephalopods - Anatomy and Adaptation

14:31 - Cephalopods - Evolutionary History

15:43 - Cephalopods - The Coleoids (Squid and Octopus)

16:41- Cephalopods - Argonaut Octopus (Paper Nautilus)

17:33 - Cephalopods - The Vampire Squid

18:41 - Conclusion

Natural World Facts
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