Selected pictures list
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A cross section of a post-
clitellum segment of an
annelid (ringed worm); almost all segments of an annelid contain the same set of organs and parts, a pattern called
metamerism. Annelids have no lungs, but rather exchange
carbon dioxide and
oxygen directly through the moist skin when blood reaches the extremely fine capillaries of the body walls; a dry worm cannot breathe and will die of suffocation. The worm's red blood, which does not consist of
platelets or
red cells but mostly of a liquid containing suspended
hemoglobin, makes a circuit up and down the animal in its closed circulatory systems.
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The
common clam worm (
Alitta succinea) is a widely distributed species of marine
polychaete worm. The photograph shows an
epitoke specimen, the worm having turned into a form capable of reproduction. After releasing its sperm or eggs, the animal will die.
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A
macro view of a
Gonia capitata fly feeding on
honey, showing its
proboscis and
pedipalps (the two appendages protruding from the proboscis), two types of
insect mouthparts. The proboscis actually comprises the labium, a quadrupedal structure, and a sponge-like labellum at the end. Flies eat solid food by secreting
saliva and dabbing it over the food item. As the saliva dissolves the food, the solution is then drawn up into the mouth as a liquid. The labellum's surface is covered by minute food channels which form a tube leading to the
esophagus, and food is drawn up the channels by
capillary action.
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A caterpillar of
Lymantria dispar dispar, also known as the gypsy moth. First described by
Carl Linnaeus in 1758, the gypsy moth is found throughout Eurasia, where it is considered a pest. The larvae emerge from egg masses in the spring, and then are dispersed by the wind and begin feeding on leaves. They are initially
diurnal, but become
nocturnal after their fourth molting.
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The
bird-cherry ermine (
Yponomeuta evonymella) is a species of moth in the family
Yponomeutidae, native to Europe and parts of Asia. The caterpillars are gregarious and feed on the leaves of the
bird cherry tree, forming silken webbing for their own protection. They create further webbing on the trunk and near the base of the tree, which hides them as they
pupate. This photograph shows one of many bird-cherry ermine caterpillar nests on a tree in
Lahemaa National Park, Estonia. In some years, they are so numerous that they can completely strip a tree of its foliage.
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Sexual dimorphism is the condition where the two
sexes of the same
species exhibit different characteristics. Differences may include
secondary sex characteristics, size, weight, color, or markings, as well as behavioral and cognitive differences. In the butterfly species
Colias dimera (also known as the Dimera sulphur), seen here mating in Venezuela, the male on the right is a brighter shade of yellow than the female.
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Photo: Charles H. Smith, USFWS
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The
Osprey (
Pandion haliaetus) is a medium large
raptor which is a specialist fish-eater with a worldwide distribution. It is often known by other
colloquial names such as Fish Hawk, Sea Hawk or Fish Eagle.
The Osprey is particularly well adapted to its diet, with reversible outer toes, closable nostrils to keep out water during dives, and backwards facing scales on the talons which act as barbs to help catch
fish.
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A female
Calliope Hummingbird (
Stellula calliope), the smallest bird found in Canada and the United States, feeding insects to chicks. Found mostly in western North America (although
vagrants have been found in New York and Connecticut), it is
migratory and winters in southwestern Mexico.
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The
brown pelican (
Pelecanus occidentalis) is a bird of the pelican family,
Pelecanidae, one of three species found in the Americas and one of two that feed by diving into water. This photograph shows a juvenile brown pelican gliding over the Pacific Ocean at
Bodega Head, California.
After hatching, the pelican chicks are fed on
regurgitated predigested fish and take about two months to fledge. When they leave the nest, they are at first unable to fly and take wing several weeks later. When the parents cease to feed them, some six months later, each will have consumed around 70 kg (150 lb) of fish. The juvenile brown pelican does not acquire adult plumage until three years of age, when the feathers on the neck become paler, the upperparts striped, the wing feathers grayer, and the belly acquires dark spots.
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The
paddyfield pipit (
Anthus rufulus) is a
passerine bird in the family
Motacillidae, comprising
pipits,
longclaws and
wagtails. About 15 cm (6 in) in length and native to southern Asia, its plumage in both sexes is greyish-brown above and paler yellowish-brown below, with dark streaking on the breast. A bird of open country, pasture and cultivated fields, it sometimes makes short flights, but mostly runs on the ground, foraging for insects and other small invertebrates. The paddyfield pipit builds its cup-shaped nest in a concealed location on the ground, and may have two or more broods in a year. This
A. r. rufulus individual was photographed in
Kanha Tiger Reserve, in the Indian state of
Madhya Pradesh.
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The
leopard shark (
Triakis semifasciata) is a species of
hound shark found along the
Pacific coast of
North America from the U.S. state of
Oregon to
Mazatlán in Mexico. Typically measuring 1.2–1.5 m (3.9–4.9 ft) long, this slender-bodied shark is characterized by black saddle-like markings and large spots over its back.
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The
Peacock flounder (
Bothus mancus) is a species of
lefteye flounder found widely in relatively shallow waters in the
Indo-Pacific. This
photomontage shows four separate views of the same fish, each several minutes apart, starting from the top left. Over the course of the photos, the fish
changes its colors to match its new surroundings, and then finally (bottom right) buries itself in the sand, leaving only the eyes protruding.
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The
Atlantic spadefish is a species of marine fish
endemic to the shallow waters off the coast of the southeastern United States and in the
Caribbean Sea. They are similar in appearance to
fresh water angelfish, but much larger, reaching up to three feet (0.9 m) in length. Due to their reputation as strong fighters, they are popular
game fish, especially during the summer months when they are most active.
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The
Common Brushtail Possum (
Trichosurus vulpecula) is the largest
possum species and is perhaps the most widespread
mammal in Australia. It grows to about 32–58 cm (13–23 in) in length, with an additional 24–40 cm (9–16 in) for its
prehensile tail (seen here hanging below the branch). It is mainly a
folivore, but has been known to eat small mammals such as rats. It is common in cities, having adapted well to human habitation.
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The
plains zebra (
Equus quagga, subspecies
Grant's zebra pictured) is the most common and geographically widespread species of
zebra. It ranges from the south of Ethiopia through East Africa to as far south as Angola and eastern South Africa. The plains zebra is mid-sized, smaller on average than the other two zebra species, and thick-bodied with relatively short legs. Adults of both sexes can stand from 1.1 to 1.47 m (3.6 to 4.8 ft) high at the shoulder, are 2 to 2.5 m (6.6 to 8.2 ft) long (excluding the tail), and weigh 175 to 387 kg (386 to 853 lb), with males slightly heavier than females.
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Photograph: Gabriel Barathieu
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The
rock hyrax (
Procavia capensis), also known as the dassie, is one of four living species of the order
Hyracoidea, and the only living species in its genus. Like all
hyraxes, it is a medium-sized terrestrial mammal between 4 kilograms (9 lb) and 5 kilograms (11 lb) in mass, with short ears and tail. The rock hyrax is found across Africa and the Middle East, at elevations up to 4,200 metres (13,800 ft). It resides in habitats with rock crevices which it uses to escape from predators. Along with the other hyrax species and the
manatee, these are the animals most closely related to the elephant.
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Eutropis macularia, the bronze grass skink, is a species of lizard in the
skink family, Scincidae, native to South and Southeast Asia. It lives in both deciduous and evergreen forests, in plantations, in grasslands, and in rocky areas with scattered trees. The species is active in both the day and the night, feeding on insects and other invertebrates. This bronze grass skink was photographed on a tree trunk on the island of
Don Det in Laos.
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Artist: H. Morin; Restoration: Citron An illustration of various
Pulmonata (and one predator
arthropod in the lower right), an informal group of
snails and
slugs characterized by the ability to breathe air, by virtue of having a
pallial lung instead of a
gill, or gills. Pulmonata was previously a formal
taxon but lost its status as one in 2010. The group includes many land and freshwater families, and several marine families. Most species have a shell, but no
operculum, although the group does also include several shell-less slugs. Pulmonates are
hermaphroditic, and some groups possess
love darts.
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Photograph: Taro Taylor; edit: Dapete Glaucus atlanticus is a species of small, blue
sea slug. This
pelagic aeolid
nudibranch floats upside down, using the surface tension of the water to stay up, and is carried along by the winds and ocean currents. The blue side of their body faces upwards, blending in with the blue of the water, while the grey side faces downwards, blending in with the silvery surface of the sea.
G. atlanticus feeds on other pelagic creatures, including the
Portuguese man o' war.
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Liguus virgineus, also known as the candy cane snail, is a species of snail in the family
Orthalicidae. It is native to the Caribbean island of
Hispaniola, in the nations of Haiti and the Dominican Republic. There have also been at least three reports of living specimens being found in the
Florida Keys of the United States. The snail lives on trees and feeds on moss, fungi and microscopic algae covering the bark.
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Haliotis laevigata is a species of marine
mollusc in the family
Haliotidae,
endemic to Tasmania and the southern and western coasts of Australia. This picture shows five views of a green
H. laevigata shell, 7.5 centimetres (3.0 in) in length. The holes in the shell, characteristic of
abalones, are respiratory apertures for venting water from the gills and for releasing sperm and eggs into the
water column.
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The
coconut octopus (
Amphioctopus marginatus) is a medium-sized
cephalopod found in tropical waters of the western Pacific Ocean. It commonly preys upon
shrimp,
crabs, and
clams, and displays unusual behaviour, including bipedal walking and gathering and using
coconut shells and seashells for shelter.
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Illustration: Ewald Rübsamen Velodona togata is the only species in the
octopus genus
Velodona; the genus and species names come from the large membranes that connect its arms. It was first described by
Carl Chun in his book
Die Cephalopoden (from which this illustration is taken) in 1915. A second subspecies was described by
Guy Coburn Robson in 1924.
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Anatomical diagram of an adult female
chambered nautilus, the best known species of
nautilus, a "
living fossil" related to the octopuses. The animal has a primitive brain that forms a ring around its
oesophagus, has four gills (all other
cephalopods have only two), and can only move shell-first (seemingly "backwards") by pumping water out through its funnel. The shell and tentacles are shown here as shadows.
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Illustration: Comingio Merculiano
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The
maxima clam (
Tridacna maxima) is a species of
bivalve found throughout the
Indo-Pacific. It is found on the surface of reefs or sand, or partly embedded in coral (as with this specimen), in the oceans surrounding east Africa, India, China, Australia, Southeast Asia and the islands of the Pacific. This clam is much sought after in the aquarium trade, as its often striking coloration—the result of crystalline pigment—mimics that of the true
giant clam.
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A
soybean cyst nematode (
Heterodera glycines), together with an egg, as viewed through a low-temperature
scanning electron microscope at 1000x magnification. This
nematode infects the roots of soybeans, and the female nematode eventually becomes a
cyst. Infection causes various symptoms that may include
chlorosis of the leaves and stems, root necrosis, loss in seed yield and suppression of root and shoot growth.
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A lateral (left side) anatomical diagram of an adult-stage nematode
hermaphrodite Caenorhabditis elegans (
full size) with emphasis on the digestive and reproductive systems.
C. elegans is a free-living, transparent
nematode (roundworm) which measures about 1 millimetre (0.039 in) in length. The hermaphrodite form, as seen here, is the most common, although a male form is also found. When self-inseminated, the species will lay about 300 eggs, but when the hermaphrodite is inseminated by a male, the number of progeny can exceed 1,000.
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Thysanozoon nigropapillosum, the yellow-spotted flatworm, is a species of marine
flatworm in the family
Pseudocerotidae. The species is native to the tropical Indo-Pacific region, where it lives in shallow reef habitats. Flatworms are
hermaphrodites, each being able to act as either male or female. As a donor of sperm, it can grip the margin of the recipient's body, using its two penises in a chopstick-like manner, and deposit sperm on the surface of the skin of the recipient, even while it is actively swimming.
This picture shows a yellow-spotted flatworm photographed in Manta Ray Bay, on the island of
Yap in the Federated States of Micronesia. The flatworm is seen swimming to the right at a depth of 12 metres (40 ft) by undulating the margins of its body. The pseudotentacles at the front have simple eyes and sensory receptors to enable the flatworm to find
tunicates on which it feeds.
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Plate 5 from
Ernst Haeckel's
Kunstformen der Natur, showing a variety of
calcareous sponges, a
class of about 400 marine
sponges that are found mostly in shallow tropical waters worldwide. Calcareous sponges vary from radially symmetrical vase-shaped body types to colonies made up of a meshwork of thin tubes, or irregular massive forms. The skeleton has either a mesh or honeycomb structure.
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Aplysina archeri is a species of
sponge that has long tube-like structures of cylindrical shape. Many tubes are attached to one particular part of the organism; a single tube can grow up to 5 feet (1.5 m) high and 3 inches (7.6 cm) thick. These sponges mostly live in the
Atlantic Ocean. These
filter feeders eat food such as
plankton or suspended
detritus as it passes them.
File:Reef3859 - Flickr - NOAA Photo Library.jpg
Credit: Twilight Zone Expedition Team 2007, NOAA-OE Sponges (also known as
sea sponges), the members of the
phylum Porifera (
pər-IF-ər-ə, por-; meaning 'pore bearer'), are a
basal animal clade as a sister of the
diploblasts.
[excessive citations] They are
multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like
mesohyl sandwiched between two thin layers of
cells. (
Full article...) Included are the yellow tube sponge,
Aplysina fistularis, the purple vase sponge,
Niphates digitalis, the red encrusting sponge,
Spirastrella coccinea, and the gray rope sponge,
Callyspongia sp.
File:Mikrofoto.de-Raedertier-14.jpg
File:Haeckel Platodes.jpg
The
flatworms,
flat worms,
Platyhelminthes, or
platyhelminths (from the
Greek πλατύ,
platy, meaning "flat" and ἕλμινς (root: ἑλμινθ-),
helminth-, meaning "
worm") are a
phylum of relatively simple
bilaterian,
unsegmented, soft-bodied
invertebrates. Being
acoelomates (having no
body cavity), and having no specialised
circulatory and
respiratory organs, they are restricted to having flattened shapes that allow
oxygen and nutrients to pass through their bodies by
diffusion. The digestive cavity has only one opening for both ingestion (intake of nutrients) and egestion (removal of undigested wastes); as a result, the
food can not be processed continuously. (
Full article...)
File:Ophiura ophiura.jpg
Brittle stars,
serpent stars, or
ophiuroids (from
Latin ophiurus 'brittle star'; from
Ancient Greek ὄφις (óphis) 'serpent', and
οὐρά (ourá) 'tail'; referring to the serpent-like arms of the brittle star) are
echinoderms in the class
Ophiuroidea, closely related to
starfish. They crawl across the sea floor using their flexible arms for locomotion. The ophiuroids generally have five long, slender, whip-like arms which may reach up to 60 cm (24 in) in length on the largest specimens. (
Full article...)
File:Haeckel Bryozoa.jpg
Bryozoa (also known as the
Polyzoa,
Ectoprocta or commonly as
moss animals) are a
phylum of simple,
aquatic invertebrate animals, nearly all living in sedentary
colonies. Typically about 0.5 millimetres (
1⁄64 in) long, they have a special feeding structure called a
lophophore, a "crown" of tentacles used for
filter feeding. Most
marine bryozoans live in tropical waters, but a few are found in
oceanic trenches and polar waters. The bryozoans are classified as the
marine bryozoans (Stenolaemata),
freshwater bryozoans (Phylactolaemata), and
mostly-marine bryozoans (Gymnolaemata), a few members of which prefer
brackish water. 5,869
living species are known. Originally all of the crown group Bryozoa were colonial, but as an adaptation to a mesopsammal (interstitial spaces in marine sand) life or to deep‐sea habitats, secondarily solitary forms have since evolved. Solitary species has been described in four
genera;
Aethozooides,
Aethozoon,
Franzenella and
Monobryozoon). The latter having a statocyst‐like organ with a supposed excretory function. (
Full article...)