Page 48 - One Million Things: Animal Life - The Incredible Visual Guide

Tentacles are Sea nettle
colonies of 4
tiny animals
Portuguese 3
man-of-war Box jellyfish

Tentacles
can inflict
SPONGES, lethal stings

JELLIES, AND CORALS

Some of the simplest members of the animal kingdom
belong to three phyla—Porifera, Cnidaria, and Ctenophora.
Beroid comb jelly
Poriferans are sponges, animals that feed by filtering food
from the water. Cnidarians include hydrozoans, jellyfish,
1 corals, and sea anemones. All have stinging tentacles that
immobilize and trap prey. Ctenophores, also known as
comb jellies, are related to the cnidarians.

1 COMB JELLIES 2 SPONGES 3 HYDROZOANS 4 JELLYFISH
Delicate and nearly transparent, The simplest of all animals, sponges This group of cnidarians shows Scyphozoans or “true” jellyfish have
comb jellies swim among the ocean are unlike any other creatures. Most astonishing variety, from animals that a bell-shaped body, filled with the
plankton. Eight rows of hairlike cilia attach themselves to the seabed, resemble tiny sea anemones to the jellylike substance that gives the
extend from top to bottom, beating where they grow without symmetry, extraordinary Portuguese man-of-war. animal its name, and prey-catching,
in waves to move the comb jelly their bodies supported by a This jellyfish is not one organism but stinging tentacles. A jellyfish swims
around. Most catch prey with two “skeleton” made of tiny struts and a colony of cooperating animals. One by contracting its body to force out
sticky tentacles, but this beroid comb peppered with pores. Water is drawn forms the prominent gas balloon that water from its underside and propel
jelly uses its mouth to eat prey whole. into the pores and food particles are allows the colony to float and drift. it in the opposite direction. Related
filtered out and digested. Others make up the tentacles. box jellyfish are notorious for their
toxic stings that can kill humans.

5 SEA ANEMONES
Opening through Water enters sponge
which water current through tiny openings They may look like colorful plants,
leaves sponge in its surface but sea anemones are predators
that eat small animals. On top of the
Yellow tube sponge Sea sponge 2 surrounded by stinging tentacles.
anemone’s body is a central mouth

A base fixes the animal to a rock.
If threatened, many anemones
rapidly expel water from their
insides and shrink dramatically.

5
Stinging
tentacles
capture prey,
then draw it into
central mouth

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