Historical Portrait Collection: A Resource for Education

Finding compelling visuals to enhance learning materials is crucial in the educational landscape. Science Source offers an exclusive collection of historical portraits tailored for textbooks, periodicals, schools, universities, and educational resources.

In-house colorization specialists:

Nicolaus Copernicus, Renaissance mathematician and astronomer.

Particularly noteworthy are the numerous meticulously hand-colored portraits by our in-house staff of illustrators and artists. These images include scientists such as Sigmund Freud, Albert Einstein, Charles Darwin, Gregor Mendel, and Isaac Newton, inventors such as Thomas Edison, Robert Oppenheimer, and Charles Darwin, and great philosophers from Immanuel Kant to Friedrich Nietzsche.

Historic Events and Personalities

Philosophers

Unique and Rare Photography Portraiture:

Our stock photography archive contains a unique array of historical portraits that capture iconic figures from various fields. The collection has notable Hollywood personalities such as Audrey Hepburn, Paul Newman, James Dean, Diane Keaton, and Elizabeth Taylor. You'll find these alongside artists like Pablo Picasso and Frida Kahlo, David Hockney, Pablo Picasso, Andy Warhol (with the Pope), and Jackson Pollack. Notaries like Julia Child, The Beatles, Elvis Presley, Pete Seeger, and even the Backstreet Boys.

Famous Personalities Gallery

Actors & Performers Gallery

World Leader Portraits

Science Source provides an extensive collection of portraits featuring influential figures from around the globe. From renowned statesmen like Colin Powell, Thomas Jefferson, Lyndon Johnson, and John F. Kennedy to iconic leaders such as Winston Churchill, Queen Victoria, and Margaret Thatcher, our archive encompasses an array of presidents, prime ministers, kings, queens, rulers, and politicians.

World Leaders

United States Presidents & First Ladies

Celebrating Black History

Martin Luther King, Jr. in a church in Atlanta, Georgia, 1968.

In addition to world leaders, Science Source proudly celebrates Black history by showcasing portraits of remarkable blacks in history. From civil rights icons like Martin Luther King and Shirley Chisholm to aviation trailblazers such as Bessie Coleman, our collection honors the contributions of black leaders, scientists, performers, and politicians. Icons like Muhammad Ali, Sidney Poitier, James Baldwin, Bessie Smith, Louis Armstrong, Ray Charles, Josephine Baker, and Jesse Owens serve as enduring inspirations, embodying resilience, talent, and courage.

Black Personalities

Martin Luther King, Jr.

Albert Einstein and his wife, Elsa.

A Legacy of Providing Historical Content for Education

Science Source has provided visual materials for the education industry for over five decades. We cover all study subjects, excelling in medicine, science, physics, chemistry, sociology, and other hard and soft science fields. For educators, Science Source's collection enriches lesson plans and classroom discussions, offering context and inspiration across disciplines.

Famous Physicians & Psychologists

Notable Scientists

Looking Forward:

As education continues to evolve, resources like Science Source's historical portraits play a vital role in fostering understanding and appreciation of our collective past. Let us utilize these images as gateways to exploration and discovery, enriching the educational journey for future generations.

Image and Video Content Pricing Customized to Your Needs

Science Source is at the forefront of providing science and medical stock content worldwide. We offer a range of pricing options, from royalty-free to rights-managed and subscription models. Reach out to us for tailored pricing. Your journey to accessing top-notch scientific imagery and content starts here.

Exploring Microscopy: Ultimate List of Microscope Types With Image Examples

A glance at any scientific or medical article reveals how far microscopy has evolved from the basic microscope of high school biology classes. Today, it's not just about magnification but also about capturing sharp details, enhancing depth of field, observing internal structures, and experiencing vivid 3D-like visuals that captivate our imagination. Over time, there have been numerous advancements in light microscopy, introducing many new types that unveil a previously unimaginable level of detail.

Stock Image Gallery of Medical Micrographs

The conventional microscope, which is familiar from childhood and known as the "light microscope," functions by utilizing light and a series of lenses. By incorporating filters, specialized mirrors, lasers, specific light spectrums, and other enhancements, we can extract significantly more detailed information.

First, let's cover a few basics:

What is Microscopy

Electron micrograph of red blood cells and fibrin. © Scoatt Camazine / Science Source

Microscopy could be defined as the scientific technique used to observe objects that are too small to be seen with the naked eye, typically using microscopes. It allows researchers to examine the structure and properties of materials and biological specimens at a microscopic level.

Magnification and Resolving Power

Magnification refers to the degree to which an object is enlarged when viewed through a microscope. It is usually expressed as a ratio (e.g., 100x), indicating how many times larger the object appears compared to its actual size.

Resolving power (or resolution) refers to the microscope's ability to distinguish between two closely spaced objects as separate entities. It determines how clearly individual details can be seen.

A Gallery of Royalty-free Micrographs

Let's start with Light Microscopes:

Four types of Light micrographs: Bright Field, Dark Field, Polarized, Phase Contrast. © Marek Mis/Science Source

Various illumination techniques are employed when examining slides under a light microscope, including Bright Field, Dark Field, Fluorescence, Differential Interference Contrast (DIC), Phase Contrast, and Confocal microscopy.

Photos of the microscopes can be found below.

Light Microscope Using Bright Field

Bright Field Microscopy: The light source is directed beneath the specimen, resulting in a brightly lit area surrounding it.

Light Microscope Using Dark Field

Dark Field Microscopy: Here, the light source is obscured, casting light onto the specimen from various angles, providing slightly different details compared to direct illumination.

Fluorescence Microscope

Fluorescence Microscopy: This technique utilizes light filters and specific wavelengths to induce fluorescence in the specimen, producing vibrant images.

Purkinje neurons of the cerebellar cortex stained with four staining methods: hematoxylin eosin (top left), cresyl violet (top right), Cajal's silver nitrate (bottom left) and silver method for Golgi apparatus (bottom right). © Jose Luis Calvo/Science Source

Phase Contrast Microscope

Phase Contrast Microscopy: By employing specialized lenses and filters, this method allows the visualization of transparent and colorless specimens with minimal shadowing.

Differential Interference Contrast Microscope

Differential Interference Contrast Microscopy (DIC): Through the use of polarizers, beam splitters, condensers, and filters, transparent specimens can be observed with a distinctly three-dimensional appearance.

Different illumination techniques of a light microscope: dark field, fluorescence, bright field, phase contrast, DIC (differential interference contrast). Child's hair strand © Ted Kinsman/Science Source

Caenorhabditis elegans (roundworm) embryo transform into a Dauer state when stressed during larval development (for instance, due to lack of food, hot environment, or crowding). Somatic cells are colored red, and yellow dots show gut granules used for fat storage. Image compiled from scans of different layers of the embryo. © Kul Bhatia / Ming Kin Wong / Science Source

Confocal Microscope

Confocal Microscopy: Utilizing Confocal Laser Scanning Microscopy (CLSM), a laser and spatial pinhole combine to produce high-resolution images with enhanced clarity.

Gallery of Botany Micrographs

Advanced types of microscopes:

Scanning electron micrograph (SEM) of Escherichia coli (E. coli), a type of Gram-negative rod-shaped bacteria that normally lives in the intestines of people and animals. Magnification is 17,500x at 15cm image size. ©Nano Creative / Science Source

Scanning Electron Microscope

Scanning Electron Microscopy (SEM): This microscope utilizes a beam of electrons to generate sharply detailed images by detecting reflected electrons off the specimen's surface within a vacuum environment, offering magnifications ranging from 20x to 30,000x with a spatial resolution of 50 - 100nm.

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Transmission electron micrograph (TEM) of bacteriophage. © Biophoto Associates / Science Source

Transmission Electron Microscope

Transmission Electron Microscopy (TEM): By passing a beam of electrons through a thinly sliced specimen, TEM reveals intricate internal structures with magnifications of up to 2,000,000x.

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Plasma membrane proteins. Colored atomic force micrograph (AFM) showing the surface of a plasma membrane. The membrane consists of a lipid bilayer with many proteins (peaks) attached to it. © PROF. DR. H.OBERLEITHNER, UNIVERSITY HOSPITAL OF MUENSTER / Science Source

Atomic Force Microscope

Atomic Force Microscopy (AFM): AFM operates by bouncing a laser off a stylus attached to a cantilever lever, which then traces the specimen's surface. Any deviations trigger sensors, generating a raster image that includes the Z-Plane. Unlike electron microscopy, AFM doesn't require a vacuum, offering versatility in various environments.

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False-color scanning tunneling micrograph (STM) of a DNA double-helix; approximately three turns of the helix are displayed in this image. © Driscoll, Youngquist, & Baldeschwieler / Caltech / Science Source

Scanning Tunneling Microscope

Scanning Tunneling Microscopy (STM): STM employs electrons based on quantum tunneling, allowing for atomic-level surface imaging in vacuum, air, water, or ambient gas environments.

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What can we look at with all of these microscopes?

Scanning Electron Micrograph (SEM) of unidentified freshwater bacteria collected from pond water. © Ted Kinsman / Science Source

Scoop up pond water or ocean water to be astonished by the plethora of living zooplankton and phytoplankton visible within a single drop using a simple light microscope.

Gallery of Phytoplankton and Zooplankton

It opens you to the wonder of cyanobacteria, blue-green algae, and ciliates like paramecium, daphnia, amoebas, and euglena. If you were lucky, you might have witnessed them conjugate and divide!

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Diatom (Stephanopyxis sp.) from a South Atlantic Ocean deep sea probe. Scanning electron microscope. © Eye of Science / Science Source

Additionally, ocean water drops allow a peek at copepods, immature mollusks, krill, algae, crustaceans, and fish in their zooplankton stage. You may also behold the breathtaking beauty of diatoms, the most common type of phytoplankton in our oceans.

Switch to a higher powered Scanning Electron Microscope (SEM) to view Water Bears, pollen, blood cells, and insects. An SEM uses a particle beam of electrons to photograph the surface of a vacuum-sealed specimen.

Transmission Electron Microscopes (TEM) allow us to see cross-sections of specimens, such as the beautiful interior of the human body, marine life, and animal and plant cells. The TEM's particle beam passes through its vacuum-sealed specimen.

Photos of Types of Microscopes More Photos of Microscopes

Light Microscope

Scanning Electron Microscope

Atomic Force Microscope

Scanning Tunneling Microscope STM

Florescence Microscope

Phase Contrast Microscope

Confocal Scanning Microscope

Transmission Electron Microscope

Gallery of Microscope Types

Applications of medical microscopy

Bone marrow cell. This micrograph shows this cell with light (inset) and electron microscope. © Jose Luis Calvo/Science Source

We can view the cells of the human body with many different microscopes. The light mic, SEM, and TEM show scientists and medical researchers different angles and aspects of the cell and its fine structures and organelles.

Microscopes help scientists study cancer - breast, ovarian, prostate, liver, and skin cancer. We can better understand skin conditions such as psoriasis and eczema. They assist in the fight against nervous, respiratory, and circulatory system diseases. And a cure for muscular conditions such as fibromyalgia and multiple sclerosis (MS), and autoimmune conditions.

The Future of Microscopy:

Microscopy methods continue to evolve, with innovations like Acoustic Microscopy, which utilizes sound waves akin to SONAR, promising exciting prospects for the future of scientific exploration.

Animal Mimicry and Camouflage in Nature

Is it a twig or an insect? A harmless moth or a scary owl? Animals have amazing tricks up their sleeves to protect themselves, take advantage of looking like another creature, or look like their environment.

Mimicry and Camouflage: Two Separate Survival Tactics

An example of mimicry is an animal appearing to be a different animal, usually a larger and stronger one, to scare off predators. The pattern on the wings of an Owl Moth (photo above) resembles the eyes and face of an owl.

Stock Images of Mimicry in Nature

A nonpoisonous Scarlet King Snake on the right, a poisonous Eastern Coral Snake on the left.

The King Snake, which is non-poisonous, has a scale pattern like that of the Coral Snake, a type of venomous snake. It tricks predators into thinking they have encountered its very dangerous relative.

Batesian Mimicry and Müllerian Mimicry

Batesian mimicry occurs when a harmless species evolves to imitate the appearance of a harmful or toxic species, gaining protection from predators. A classic example is the viceroy butterfly, which resembles the toxic monarch butterfly, thus deterring potential predators.

Müllerian mimicry involves two or more harmful or unpalatable species evolving to resemble each other. This shared appearance reinforces learned avoidance by predators, increasing the overall effectiveness of the warning signals. For instance, several species of stinging bees and wasps share similar coloration patterns, serving as a collective deterrent to predators.

Animal Camouflage or Cryptic Camouflage

Dead leaf katydid, Typophyllum sp., juvenile hidden on dead leaf, amazon.

Camouflage is the art of blending into the environment to avoid detection by predators or prey. Typical examples are moths, such as the peppered moth, which looks like tree bark, or walking stick insects that resemble twigs.

Cryptic camouflage is when animals mimic specific elements of their environment, such as texture, color, or pattern. This can be seen in species like the leaf-tailed gecko, which boasts skin textures resembling tree bark, allowing them to blend into their arboreal habitats seamlessly.

The Dead Leaf Katydid is a beautiful example of camouflage. It looks just like the dead leaves it lives on. They range in appearance from a fresh green life to a rotten, decayed leaf.

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Color Changing Skills

One of the most amazing examples is the octopus, which can change its color and skin texture to hide in various underwater environments within seconds.

Beneath their skin, octopi have cells called chromatophores. Each is a sac filled with either red, orange, brown, yellow, or black pigment. These can be inflated or deflated as needed.

Video of an Octopus Changing Color

Leaf Chameleon, Brookesia thieli, Madagascar showing color change camouflage to match the branch it is clinging to. © Francesco Tomasinelli / Science Source

Chameleons are well known for their ability to change their colors to match their environment.

Green or Carolina Anole, Anolis carolinensis, changing colors. © ER Degginger / Science Source

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Concealing Coloration

Arctic fox in the winter snow, Norway. An example of concealing coloration. © Dr P. Marazzi / Science Source

When an animal’s color matches its surroundings, it is concealing coloration. Examples of this include the polar bear, arctic fox, and a snowshoe hare.

Animals can look like rocks, thorns, twigs, flowers, and bird droppings.

Animal mimicry is found throughout the animal and even plant worlds.

Studying mimicry and camouflage provides valuable insights into evolutionary biology, predator-prey dynamics, and ecosystem interactions. The world of animal mimicry and camouflage is a testament to the ingenuity of evolution.