![Carder bee - felted nesting materia IMG 0273s](https://upload.wikimedia.org/wikipedia/commons/8/8e/Carder_bee_-_felted_nesting_materia_IMG_0273s.JPG)
A felted material is a hairy or
filamentous (hairy-like) fibre that is densely packed or tangled, forming
felt
Felt is a textile material that is produced by matting, condensing and pressing fibers together. Felt can be made of natural fibers such as wool or animal fur, or from synthetic fibers such as petroleum-based acrylic or acrylonitrile or wood ...
or felt-like structures.
Anatomy and zoology
The
dermis is described in
Gray's Anatomy as "felted connective tissue, with a varying amount of elastic fibers and numerous blood vessels, lymphatics, and nerves."
When describing the external coat of an artery (the ''
tunica adventitia
The tunica externa (New Latin "outer coat"), also known as the tunica adventitia (New Latin "additional coat"), is the outermost tunica (layer) of a blood vessel, surrounding the tunica media. It is mainly composed of collagen and, in arteries, i ...
''), Gray said that it "...consists mainly of fine and closely felted bundles of white connective tissue..."
In such classes of
connective tissue the felted structure helps with resistance to tearing by distributing localised
stresses, and it imparts
shock
Shock may refer to:
Common uses Collective noun
*Shock, a historic commercial term for a group of 60, see English numerals#Special names
* Stook, or shock of grain, stacked sheaves
Healthcare
* Shock (circulatory), circulatory medical emergen ...
absorption and
elasticity in two or three dimensions at once regardless of the shape of the tissue.
In other words, certain types of felting can yield controllable
isotropy
Isotropy is uniformity in all orientations; it is derived . Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix ' or ', hence ''anisotropy''. ''Anisotropy'' is also used to describe ...
or
anisotropy
Anisotropy () is the property of a material which allows it to change or assume different properties in different directions, as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physic ...
in the behaviour of a structure.
Mammals
![Down Awn and guard hairs of cat 2012 11 13 9203r](https://upload.wikimedia.org/wikipedia/commons/d/de/Down_Awn_and_guard_hairs_of_cat_2012_11_13_9203r.JPG)
Although truly felted hair on healthy mammals is unusual, many animals, especially in seasonally cold or wet climates or environments, have a so-called undercoat of
down hair
Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket ...
plus
awn hair
Awn hairs are the intermediate hairs in a mammal's coat. They are shorter than the guard hairs and longer than the down hairs. They help with insulation and protect the down hairs underneath. Most of the visible coat is made of this kind of hair ...
that usually lies hidden beneath the outer coat of guard hairs
and may form a mat of lightly felted wool. Such down hairs as a rule are crimped into a finely woolly texture and contain waxy, water-repellent
lanolin
Lanolin (from Latin 'wool', and 'oil'), also called wool yolk, wool wax, or wool grease, is a wax secreted by the sebaceous gland
A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an ...
. In a mass they serve to retain insulating air and exclude water. In many species that live in seasonally frigid zones the winter down hair is shed in clumps during springtime. Herders can collect the wool for commercial purposes without the need for shearing.
The ground-dwelling mice species of the genus ''
Mus'' in parts of Africa build spherical nests of assorted fibres in burrows or under large flat objects. Rabbits, in particular ''
Sylvilagus
Cottontail rabbits are the leporid species in the genus ''Sylvilagus'', found in the Americas. Most ''Sylvilagus'' species have stub tails with white undersides that show when they retreat, giving them their characteristic name. However, this ...
'' species, use their own fur as a major component of their nesting material.
The
least weasel (''Mustela nivalis''), a predatory mammal, collects fur from its prey or occupies prey nests already lined; the fur forms a felted nest lining.
Birds
![Common eider nest](https://upload.wikimedia.org/wikipedia/commons/4/47/Common_eider_nest.JPG)
Weaver birds of the family
Ploceidae
Ploceidae is a family of small passerine birds, many of which are called weavers, weaverbirds, weaver finches and bishops. These names come from the nests of intricately woven vegetation created by birds in this family. In most recent classifica ...
weave nests that are lined with downy materials that become felted, both with each other and with the surrounding nest material. Sparrows build twiggy nests and line them with downy material. Other birds do little weaving in building their nests but instead construct their nests mainly of fibrous and downy materials such as fine wool, moss, lichen, spiders' nests, tufts of cotton,
arachnoid
Arachnoid may refer to:
* Relating to arachnids
* Arachnoid (astrogeology), a geological structure found only on the planet Venus
* Arachnoid (botany), referring to organs with a cobwebby exterior appearance
* Arachnoid granulation, small protrus ...
fluff, or bark scales, that are supported by twigs or the walls of burrows. Naturalist
James Rennie remarked, "A circumstance also never neglected, is to bind the nest firmly into the forks of the bush where it is placed, by twining bands of moss, felted with wool, round all the contiguous branches, both below and at the sides." Goldfinches (''
Carduelis
The genus ''Carduelis''
is a group of birds in the finch family Fringillidae.
The genus ''Carduelis'' was introduced by the French zoologist Mathurin Jacques Brisson in 1760 by tautonomy based on Carl Linnaeus's specific epithet for the Europe ...
'' species) make felted nests.
Hummingbirds do the same with spider webs and moss. Small warbler-like birds of the genera ''
Prinia
Prinia is a genus of small insectivorous birds belonging to the passerine bird family Cisticolidae. They were at one time classed in the Old World warbler family, Sylviidae.
The prinias are sometimes referred to as wren-warblers. They are a ...
'' and ''
Cisticola
__NOTOC__
Cisticolas (pronounced ''sis-TIC-olas'') are a genus of very small insectivorous birds formerly classified in the Old World warbler family Sylviidae, but now usually considered to be in the separate family Cisticolidae, along with other ...
'' make their nests either heavily lined with, or entirely of, felted material.
Ground nesting birds often use felted material rather than woven. For example, the
common eider
The common eider (pronounced ) (''Somateria mollissima''), also called St. Cuthbert's duck or Cuddy's duck, is a large ( in body length) sea-duck that is distributed over the northern coasts of Europe, North America and eastern Siberia. It breed ...
(''Somateria mollissima''), famous for the valuable down harvested from its abandoned nests, lays its eggs in very lightly felted bowls of its own down for insulation.
Invertebrates
![Cochenille z02](https://upload.wikimedia.org/wikipedia/commons/2/20/Cochenille_z02.jpg)
The
integument
In biology, an integument is the tissue surrounding an organism's body or an organ within, such as skin, a husk, shell, germ or rind.
Etymology
The term is derived from ''integumentum'', which is Latin for "a covering". In a transferred, or ...
of some insects can be coated with a felted material. It is not usually living tissue but consists of waxy fibres that serve as protection from either excessive desiccation or moisture. It is common in some families of the
Hemiptera (true bugs). In some species it occurs only as an outer coat of the immature insect, but in others, such as many of the
Coccoidea
Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than t ...
, including the cottony cushion scale ''
Icerya purchasi'' and the
cochineal
The cochineal ( , ; ''Dactylopius coccus'') is a scale insect in the suborder Sternorrhyncha, from which the natural dye carmine is derived. A primarily sessile parasite native to tropical and subtropical South America through North Americ ...
of genus ''
Dactylopius
''Dactylopius'' is a genus of insect in the superfamily Coccoidea, the scale insects. It is the only genus in the family Dactylopiidae.Van Dam, A. R. and B. May. (2012)A new species of ''Dactylopius'' Costa (''Dactylopius gracilipilus'' sp. nov.) ...
'', it is secreted throughout the life of the insect and serves largely to protect the eggs rather than the insect itself.
In other species, such as many of the woolly aphids of subfamily
Eriosomatinae
Woolly aphids (subfamily: Eriosomatinae) are sap-sucking insects that produce a filamentous waxy white covering which resembles cotton or wool. The adults are winged and move to new locations where they lay egg masses. The nymphs often form la ...
, the most fluff is borne on the adult insect.
Burying beetle
Burying beetles or sexton beetles, genus ''Nicrophorus'', are the best-known members of the family Silphidae (carrion beetles). Most of these beetles are black with red markings on the elytra (forewings). Burying beetles are true to their name†...
s of genus ''Nicrophorus'' are known for stripping the fur or feathers from the carcasses that they prepare for their young, then using the material to line and reinforce the crypt that they dig.
It is unclear if this habit is incidental or how important it is to the species. French naturalist and entomologist
Jean-Henri Fabre
Jean-Henri Casimir Fabre (21 December 1823 – 11 October 1915) was a French naturalist, entomologist, and author known for the lively style of his popular books on the lives of insects.
Biography
Fabre was born on 21 December 1823 in Saint-L ...
demonstrated that the species he investigated did not depend on feathered or hairy food items and were capable of using reptiles, amphibians and fish.
Carder bees of family
Megachilidae
Megachilidae is a cosmopolitan family of mostly solitary bees. Both that their pollen-carrying structure (called a '' scopa'') is restricted to the ventral surface of the abdomen (rather than mostly or exclusively on the hind legs as in other ...
build their nests using fibre collected from
arachnoid
Arachnoid may refer to:
* Relating to arachnids
* Arachnoid (astrogeology), a geological structure found only on the planet Venus
* Arachnoid (botany), referring to organs with a cobwebby exterior appearance
* Arachnoid granulation, small protrus ...
plants, and possibly fibre from other sources such as animal wool.
![Ctenizidae Cork-lid Trapdoor spider dwelling IMG 4025s](https://upload.wikimedia.org/wikipedia/commons/9/9f/Ctenizidae_Cork-lid_Trapdoor_spider_dwelling_IMG_4025s.JPG)
Spider egg cases are partly or largely felted silk. The lids of various species of
trapdoor spider
Trapdoor spider is a common name that is used to refer to various spiders from several different groups that create burrows with a silk-hinged trapdoor to help them ambush prey.
Several families within the infraorder Mygalomorphae contain trapdo ...
burrows vary in their construction, but they are largely of earth and similar material reinforced with partly felted silk.
Botany
![Jardin des plantes Paris Cephalocereus senilis](https://upload.wikimedia.org/wikipedia/commons/4/4b/Jardin_des_plantes_Paris_Cephalocereus_senilis.JPG)
In botany, ''felted'' is defined as "matted with intertwined hairs".
A felted covering is protective against grazing or browsing, wind, windblown sand, ultraviolet radiation, drought, and desiccation. An example is ''
Cephalocereus senilis
''Cephalocereus senilis'', the old man cactus, is a species of cactus native to Hidalgo and Veracruz in central Mexico. It is threatened in the wild, but widespread propagation and popularity in cultivation have reduced the demand on wild popul ...
'' (old man cactus), which has radial spines that grow into a tangled coating of white hair, concealing the green tissue and the spines. The felt forms a protection against intense radiation, wind, frost, and herbivores.
The woolly masses of fibres on such cacti have been used as stuffing for pillows.
Mycology
![Amanita muscaria G2](https://upload.wikimedia.org/wikipedia/commons/d/d8/Amanita_muscaria_G2.jpg)
Most fungal tissue is filamentous, predisposing it to grow into tangles that lend themselves to felting. Most mushroom tissue, including cords and membranes, is formed of
anastomosed and felted hyphae. The spots on the caps of ''
Amanita muscaria'' consist of felted patches of remnant tissue from the
volva.
References
{{Reflist
Insect morphology
Plant morphology