Editing Sponge (section)

=== Habitats ===

{{See also|Sponge ground|Sponge reef}}

[[File:Euplectella aspergillum (cropped).jpg|thumb|''[[Euplectella aspergillum]]'' is a [[deep ocean]] [[glass sponge]], seen here at a depth of {{convert|2,572|m}} off the coast of [[California]]]]

Sponges are worldwide in their distribution, living in a wide range of ocean habitats, from the polar regions to the tropics.<ref name="Bergquist_2001"/> Most live in quiet, clear waters, because sediment stirred up by waves or currents would block their pores, making it difficult for them to feed and breathe.<ref name="Krautter_1998"/> The greatest numbers of sponges are usually found on firm surfaces such as rocks, but some sponges can attach themselves to soft sediment by means of a root-like base.<ref>{{cite journal |last1=Weaver |first1=James C. |last2=Aizenberg |first2=Joanna |last3=Fantner |first3=Georg E. |last4=Kisailus |first4=David |last5=Woesz |first5=Alexander |last6=Allen |first6=Peter |last7=Fields |first7=Kirk |last8=Porter |first8=Michael J. |last9=Zok |first9=Frank W. |last10=Hansma |first10=Paul K. |last11=Fratzl |first11=Peter |last12=Morse |first12=Daniel E. |title=Hierarchical assembly of the siliceous skeletal lattice of the hexactinellid sponge Euplectella aspergillum |journal=Journal of Structural Biology |volume=158 |issue=1 |date=2007 |doi=10.1016/j.jsb.2006.10.027 |pages=93–106|pmid=17175169 }}</ref>

Sponges are more abundant but less diverse in temperate waters than in tropical waters, possibly because organisms that prey on sponges are more abundant in tropical waters.<ref>{{cite journal |last1= Ruzicka |first1=R |last2=Gleason |first2=D.F. |title=Latitudinal variation in spongivorous fishes and the effectiveness of sponge chemical defenses |journal=Oecologia |volume=154 |issue=4 |pages=785–94 |date=January 2008 |pmid=17960425 |doi=10.1007/s00442-007-0874-0 |url=http://www.bio.georgiasouthern.edu/Bio-home/Gleason/Ruzicka&Gleasonfulltext.pdf |archive-url=https://web.archive.org/web/20081006123601/http://www.bio.georgiasouthern.edu/Bio-home/Gleason/Ruzicka%26Gleasonfulltext.pdf |url-status=dead |bibcode=2008Oecol.154..785R |s2cid=1495896 |archive-date=2008-10-06 }}</ref> [[Glass sponge]]s are the most common in polar waters and in the depths of temperate and tropical seas, as their very porous construction enables them to extract food from these resource-poor waters with the minimum of effort. [[Demosponge]]s and [[Calcarea|calcareous sponges]] are abundant and diverse in shallower non-polar waters.<ref>{{cite book |last1=Gage |first1=J.D. |last2=Tyler |first2=P.A. |title=Deep-sea Biology: A Natural History of Organisms at the Deep-Sea Floor|publisher=[[Cambridge University Press]] |pages=91–93 |year=1996|isbn=978-0-521-33665-9|url={{google books |plainurl=y |id=kHZO5igKhsAC}}}}</ref>

The different [[Class (biology)|classes]] of sponge live in different ranges of habitat:
{{Clear}}
:{|class="wikitable"
|-
! [[Class (biology)|Class]] !! Water type<ref name="Bergquist_1998"/> !! Depth<ref name="Bergquist_1998"/> !! Type of surface<ref name="Bergquist_1998"/>
|-
! [[Calcarea]]
|Marine ||less than {{convert|100|m|ft|abbr=on}} ||Hard
|-
! [[Glass sponge]]s
|Marine ||Deep ||Soft or firm [[sediment]]
|-
! [[Demosponge]]s
|Marine, brackish; and about 150 freshwater species<ref name="Ruppert_2004"/> ||Inter-tidal to abyssal;<ref name="Bergquist_1998"/> a carnivorous demosponge has been found at {{convert|8840|m|mi|abbr=on}}<ref name="Vacelet_1995"/> ||Any
|}