A weekly image selected from the striking imagery produced every day by scientists around the world.
Image of the Week is a feature of the HHMI BioInteractive website. A different image will be posted each week in order to highlight topics in the Life and Earth Sciences. Each of the images will be accompanied by a short description together with information about the author and web links for further study. The images will be archived on the HHMI BioInteractive website, and will be made freely available for download from a searchable database for educational purposes. For more info on Image of the Week or how to submit, consult the Related Materials to the right.
In This Series (57)
The early embryonic cells of the sand dollar are caught in the act of synchronized cell division.
The surface cells of tadpole embryos have cilia that move the water around them.
A new technique tracks thousands of cells in the fruit fly (Drosophila) embryo during development.
Pikas are small mammals related to rabbits that can only live in cold climates, either at high latitude or high elevations in...
When heated to a temperature of around 180°C, corn bursts open with a “pop” in mere hundredths of seconds.
Many groups of organisms, including some diatoms, are radially symmetrical, and look like circles when seen end on.
Adventurer naturalist Roy Chapman Andrews (center) inspects a nest of fossil dinosaur eggs in the Gobi Desert, Mongolia in...
A tree scorpion illuminated with UV light gives off a blue-green glow.
The muscles of the mouse’s heart contract about 600 times per minute, or a billion times in its three-year lifespan.
As a student of divinity at Cambridge University, Charles Darwin was an enthusiastic collector of beetles
The measles virus can spread easily among people who have no immunity against it, as the current outbreak shows.
The Plymouth anole (Anolis lividus) lizard is found only on the Caribbean island of Montserrat—and it is the only...
A freshwater snail infected with thousands of blood flukes will release the disease-causing parasites into the water where...
Tracking the flight paths and speeds of fruit flies in a wind tunnel may help design better flying robots.
A germ-spreading sneeze unleashes a shower of large liquid droplets and a moist gas cloud of smaller ones.
Fluorescence microscopy reveals bacterial communities in human dental plaque.
Fat is made up of spherical plump cells supplied by a network of blood vessels.
One of the largest populations of Nile crocodiles in Africa congregates on the beaches of Lake Urema in Gorongosa National...
Using super-resolution microscopes, scientists have uncovered how single protein molecules behave, and the results are...
Killer T-cells captured in the act of destroying HIV-infected cells.
A reconstruction of Anchiornis huxleyi, a feathered dinosaur that is part of the ancestral lineage of birds.
During the larval stage, the Nemertean worm develops inside a hollow sac from which the juvenile eventually emerges, rupturing...
The skull of Zinjanthropus is one of the first early hominid fossils found in Africa and provides essential clues in the story...
This short-tailed fruit bat embryo shows a pattern of bones in its limbs characteristic of all tetrapods: one bone, two bones...
Two views of a late pupa of an unidentified midge species (family Chironomidae).
Reef-building corals depend on brown-colored symbiotic algae for survival.
Pushing the limits of light microscopy to the nanoscale, new technology allows visualization of single proteins in cells.
Zebrafish blood is generated from stem cells located in the tail region of fish embryos and later from stem cells located in...
A close-up view of the sound-producing structure on the wing of a field cricket (Gryllus pennsylvanicus).
Dutch draper Antonie van Leeuwenhoek (1632–1723) built microscopes that allowed him to observe never-before-seen...
Zebras on the move in a remote area of Gorongosa National Park in 2006.
Weaver ants labor to carry a live land snail back to their nest in Gorongosa National Park.
Gorongosa National Park is rich in diverse species including some found only in and near the park, like this pygmy chameleon...
A unique group of cells in the eye’s retina specifically detects the upward motion of objects, such as a ball thrown in the...
The bill of the buff-tailed sicklebill hummingbird is perfectly shaped to collect nectar from deep within the Centropogon...
A 3D model of the dengue virus reveals a shape like a soccer ball with an outer coating of glycoproteins.
The male peacock spider performs a spectacular dance to attract a mate—but the female is not always impressed.
The arrangement of cells in the retina reveals how it detects, processes, and relays visual information to the brain.
The human immunodeficiency virus (HIV) is discovered “hiding” between the cells of the gut.
Chromosomes change form as a cell divides to ensure that each daughter cell gets a full, intact copy of the genome.
Infant lemurs hitch a ride through the forest by holding on to their mother’s tummy or riding piggyback.
Female peacock spiders stay with their young in an egg sac until they can fend for themselves.
... but that's not all they'll do. Several genes determine the diverse shapes and functions of crustacean appendages.
Tiktaalik roseae, also known as the “fishapod,” is an animal that lived about 375 million years ago, with features of...
The young starlet sea anemone forms tentacles by cell division, migration, and shape changes.
Many animals have a third eyelid called a nictitating membrane that protects the eye.
The developing brain needs a constant source of new cells as it builds the circuits that will control behavior.
The golden birdwing provided a striking clue to the natural origin of species.
An intricate three-dimensional network of blood vessels nourishes the heart.
A group of 14 stink bug eggs attached to the underside of a poplar leaf.