This gallery (1) is the first area of the exhibition of live animals and is dedicated to the marine invertebrates from the Portuguese coast. The group of animals that is commonly known as 'invertebrates' includes organisms considered to be more primitive, which do not have a notochord, as opposed to 'vertebrates', a group which includes organisms considered to be more evolved, those that do have a notochord (such as fish and mammals). Invertebrates encompass a great diversity of taxonomic groups that emerged in the sea and evolved, giving rise to organisms with progressively more complex morphological characteristics, long before the appearance of vertebrates.
The Invertebrate Gallery displays species of marine fauna from the Portuguese coast, representing some of the largest taxonomic groups that inhabit the oceans. These species are arranged in 19 small aquariums, each with a volume of approximately 100 litres, in order to show the evolutionary path starts with the most primitive invertebrates (Spongia) and ends with vertebrates (represented by some species of Chordates), including some of the largest groups of invertebrates (Cnidaria, Annelida, Arthropoda, Mollusca, and Echinodermata).