![\"Acorn](\"http:\/\/sites.evergreen.edu\/vms\/wp-content\/uploads\/sites\/139\/2015\/11\/barnacle.jpg\")
<\/a>Acorn barnacle 1.7 cm by Nantz McMillen<\/p><\/div>\n
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Classification<\/h3>\n
Kingdom: Animalia
Phylum: Arthropoda
Class: Maxillopoda
Order: Sessilia
Family: Balanidae
Genus: Balanus
Species: Glandula<\/p>\n
Information<\/h3>\n
Balanus<\/em> glandula, otherwise known by their common name, acorn barnacles are crustaceans that typically live in the intertidal zone. While they are capable of living at depths of 1000m,\u00a0they usually take up residency closer to shore. Barnacles have impermeable shells, which prevent water loss when the tide goes out. \u00a0In their adult form, they continuously grow calcified plates to their shell, which is protected by a cuticle\u00a0that\u00a0they occasionally molt. They are resilient creatures but do have predators, which include ochre stars, chitons, and moon snails. \u00a0They have a primitive naupliar eye that is photosensitive,\u00a0allowing them to detect when predators are nearby. They spend their larval stage floating with plankton until they are mature enough to attach themselves permanently to a surface. They have cement glands at the base of their first antennae, which essentially allows them to cement themselves to a surface by means of their forehead. Barnacles use their cirri, feathery like appendages, to grab plankton which they pull back into the safety of their shell. \u00a0<\/p>\n Barnacles\u00a0live in nearly every body of seawater on the planet. \u00a0They have adapted to hitch rides on ships and even baleen whales, forming a commensalistic relationship with them. \u00a0While colonies of barnacles attached to ships can create drag and must be removed for the sake of time and energy efficiency, it has been described\u00a0as being less of a problem for whales. \u00a0This relationship benefits the barnacle as it travels through nutrient dense water filled with plankton, as it is the whale’s primary food source, and the whale is generally unaffected.<\/p>\nAdaptations\u00a0<\/h3>\n