Botanists on a field trip, collecting plant specimens in a herbarium press.

Herbarium

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A herbarium is a building that contains a collection of dried plant samples commonly referred to as plant specimens. Herbaria are responsible for maintaining the extensive collection of pressed, dried plant voucher specimens mounted on boards and labelled for scientific studies.

Thousands of herbarium plant specimens have been collected all around the world. These specimens are dried and carefully mounted on cardboard sheets along with the information relating to who collected them and where and when they were collected. The specimens are filed in shelves in large cupboards according to which plant family they belong to.

Herbarium plant specimens are used to describe species. Each specimen represents how a specific plant species looks like in the different areas where it has been collected.

They also inform us about the distribution of individual species over time. The species distribution is plotted on a map. Each specimen of a specific plant species is represented by a dot on a map.

Great White Shark (Carcharodon carcharias)

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The Great white sharks are the largest known predatory fish and are probably South Africa's most famous shark family, playing a significant role at the top of the marine food chain. The Great white sharks are found worldwide in temperate and subtropical waters. In South Africa, Great whites are most frequent in False Bay, Gansbaai, Mossel Bay and Bird Island in Algoa Bay. They have a large torpedo-shaped, streamlined body and for steering and balancing they use their caudal and pectoral fins. They cruise seamlessly through water for long periods of time but can swim very fast in order to catch prey. The back of their bodies have a grey colour and the front of their body is white. The mix of these two colours acts a protective camouflage when they hunt for prey, they are able to blend in with their surrounding environment and remain unnoticeable.

The great white shark has no parental care. At birth the pups (baby sharks) are as long as an adult male (1.5m) are able to look after themselves and hunt for their own food. Pups feed on fish, cephalopods like squid and octopus. Many pups do not survive the first twelve months as they get preyed upon by bigger predators including other great white sharks. Adult great white sharks feed on bony fish and sea mammals (mainly sea lions, seals and dolphins).

They have no movable eyelids but protect their eyes by rolling them backwards when feeding. The teeth of the Great White are large, with a jagged edge like a saw or similar to the blades of a saw or sharp bread knife edges. Despite having 300 teeth, they do not chew their food but rip their prey into small-sized pieces that are swallowed whole. The hunting of Great white sharks for their fins, teeth and as trophies in South African waters is prohibited as they are listed as Vulnerable species on the International Union for Conservation of Nature (IUCN) Red List of threatened species.

The South African Institute for Aquatic Biodiversity (SAIAB) supports research on white Great white sharks. The Great white is among the 22 species of sharks tagged through SAIAB’s Acoustic Tracking Array Platform (ATAP) to gather more information on shark movements and population size. Information gathered by ATAP researchers is also used to facilitate the most effective protection of this species as well as the fragile marine ecosystems in which they live in by informing the government on critical areas they use as their habitat – government is then able to develop what is known as Marine Protected Areas (MPAs). MPAs are areas of the coastline or ocean that are specially protected for the benefit of people and the marine animals living there by not allowing certain activities such as fishing in those areas.

The SAIAB’s National Fish Collection has 5 catalogued specimens, 5 jaws of the Great White shark including the only record of the albino great white shark. The SAIAB’s National Aquatic Biobank has about 20 tissue samples of Great white sharks and these form part of the resource for researchers who study the naming, defining and classifying fish based on their shared characteristics.

Southern Right Whale

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Hanging from the ceiling in the Marine Hall at Bayworld Museum in Gqeberha, is the 20 metre long, complete and articulated skeleton of a southern right whale, Eubalaena australis. This was only the second marine mammal specimen collected by the museum. It arrived in 1901. At that time there was still an open boat whaling industry in Algoa Bay. When whales were sighted in the bay from the hills surrounding the then Port Elizabeth (now the city of Gqeberha), small boats would set off from the shore. This was a dangerous business, with whalers using hand-launched harpoons to kill the whales. Many lost their lives. If successful, the dead whale would be towed back to shore to be dismembered by one of the various whaling firms based in the Bay. On the 12th of November 1901, a whaling boat from the firm, the Messina Brothers, brought back this whale. The skeleton was likely cleaned at the whaling station before being transferred to the museum. And this skeleton has travelled with the museum over the years, being displayed wherever the museum was located. 120 years later, it still continues to make people wonder and inspire scientific curiosity, in older researchers, or eager schoolchildren alike.

The southern right whale is a baleen whale. Baleen whales sieve planktonic creatures from the water using "whalebone" in their mouths. Southern right whales feed almost entirely on zooplankton, particularly krill. They feed just beneath the water's surface, holding their mouths partially open and continuously skimming water as they swim. To catch their prey, they strain the water through their long baleen plates. The baleen of a southern right whale can be up to 2.8 m long and is made up of 220-260 baleen plates.

The southern right whale, is listed as "endangered" by CITES, and is protected by all countries with known breeding populations (Argentina, Australia, Brazil, Chile, New Zealand, South Africa and Uruguay).

Fungi

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Fungi are all around us, in the soil, our bodies and the air, but are often too small to be seen with the naked eye. There are 120,000 classified types of fungi. Scientists estimate that there are 2.2 – 3.8 million species in total, including mushrooms, yeast, lichens, rust, and mold.

Fungi are non-motile, heterotrophic (no chlorophyll), unicellular (yeast) or filamentous (fungus), reproduce by means of spores, consist of long thread-like structures known as hyphae that form a mesh-like structure called mycelium.

Some play an important role in the decomposition of organic material and nutrient cycling in nature, while others form symbiotic relationships with plants. Others are plant or animal pathogens or endophytes (living inside a plant). They also serve as a food source for a large variety of organisms, including humans.

They occur in most habitats from the Arctic to Antarctica, from high mountain tops to desert sand. Some even lives in marine and fresh water environments. More than 90% of the estimated 3.8 million fungi in the world are currently unknown to science.

Did you know?
1. A fungus lives in symbioses with algae and this beneficial lifeform is called a lichen.
2. Fungi are in a kingdom of their own but are closer to animals than plants.
3. They have chemicals in their cell walls shared with lobsters and crabs.
4. There is evidence to suggest that yeasts - a type of fungus - were being used to produce the alcoholic drink mead as long ago as 9,000 years ago.
5. Products made from fungi can be used as replacements for polystyrene foam, leather and building materials.
6. DNA studies show that there are thousands of different fungi in a single sample of soil, many of which are unknown and hidden.
7. They are 2-10µm in size.
8. A huge underground fungus that is one of the largest living organisms on the planet. It spanned at least 0.37 square kilometres .It was estimated in 1980 to be at least 1500 years old and weighed at least 100,000 kilograms.
9. Fungi affects every part of your life, what you eat, what you wear, what you do and your mood.
10. Mycorrhizal fungus forms an essential symbiotic relationship with plant roots. Mycorrhizal fungi help tree and shrub roots find water and nutrients. In return, the roots give the fungi carbon, carbohydrates, and other nutrients.
11. Mushrooms and other fungi release an incredible amount of spores into the atmosphere every year, and contributing up to 50 million tonnes of particulates.

The embryos in the Bernard Price Institute collection of Karoo vertebrates at the Evolutionary Studies Institute of the University of the Witwatersrand.
Photo: Ilse van der Merwe, NSCF

Dinosaur Eggs with Embryos

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Eggs with embryos belonging to the southern African dinosaur Massospondylus were discovered in 1978 from a road cut-away in the Golden Gate National Park in the Free State.

A clutch of six eggs was removed but these were surrounded by a rock matrix. The scientists believed that attempting to remove the eggs would damage them. Xrays revealed the presence of embryos, but these remained hidden until 2005 when these eggs were carefully partially prepared out of the rock. Once the detail of the structure of the embryos was revealed, scientists were able to improve their understanding about the development of this remarkable dinosaur.

These dinosaurs lived in the early Jurassic, between 200 and 183 million years ago. measured around 4 metres in length and weighing around 1000 kilogrammes, though some sources estimate its length as high as 6 metres. It had a slender body, a long neck, and a relatively small head.

Most recently, Wits scientists (Chapelle et al., 2021) utilised the high-powered and intense energy of the European Synchrotron Radiation Facility (ESRF), located at Grenoble in France to unscramble the embryonic development of dinosaurs. These embryos are in the Bernard Price Institute collection of Karoo vertebrates at the Evolutionary Studies Institute (ESI) of the University of the Witwatersrand.

Mercury

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Mercury, the closest planet to the Sun, is a fascinating world of extremes. It's the smallest planet in our solar system, with a diameter just a bit larger than Earth's Moon. Despite its diminutive size, Mercury is a fiery planet, experiencing temperatures that range from scorching hot to freezing cold. During the day, when Mercury faces the Sun, temperatures can soar up to a blistering 800 degrees Fahrenheit (430 degrees Celsius). However, at night, when Mercury turns away from the Sun, temperatures plummet to a bone-chilling minus 290 degrees Fahrenheit (minus 180 degrees Celsius).

Mercury is a rocky planet with a heavily cratered surface, resembling the surface of Earth's Moon. Its surface features include vast plains, towering cliffs, and deep craters formed by impacts from asteroids and comets. The planet's lack of atmosphere means there is no protection from these impacts or from the Sun's intense radiation.

Despite its proximity to the Sun, Mercury is not the hottest planet in our solar system. That title goes to Venus, the second planet from the Sun. However, Mercury does have the greatest temperature variation between its day and night sides, making it one of the most extreme environments in our solar system.

Venus

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Venus, often called Earth's "twin" due to its similar size and composition, is a mysterious and inhospitable world. It is the second planet from the Sun and is often referred to as the "morning star" or the "evening star" because it is one of the brightest objects in the night sky. Despite its beauty when viewed from Earth, Venus is a hostile planet with surface temperatures hot enough to melt lead.

The surface of Venus is shrouded in thick clouds of sulfuric acid, making it impossible to see the planet's surface with the naked eye. These clouds trap heat from the Sun, creating a runaway greenhouse effect that has caused Venus to become the hottest planet in our solar system, even hotter than Mercury.

Beneath its toxic atmosphere, Venus has a rocky surface with vast plains, towering mountains, and deep valleys. It is home to numerous volcanoes, including the massive Maxwell Montes, which is the highest mountain on Venus. The planet's surface is littered with volcanic features, indicating a history of volcanic activity.

Despite its extreme conditions, scientists are intrigued by Venus and continue to study its atmosphere and surface using spacecraft and telescopes. Understanding Venus could provide valuable insights into the processes that shape rocky planets and help scientists better understand the potential for life beyond Earth.

Earth

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Earth, our home planet, is a unique and vibrant world teeming with life. It is the third planet from the Sun and the only planet in our solar system known to support life. Earth's surface is covered in vast oceans, lush forests, towering mountains, and sprawling deserts, creating a diverse and dynamic environment.

One of the most remarkable features of Earth is its atmosphere, which is composed primarily of nitrogen and oxygen. This atmosphere acts as a protective shield, filtering out harmful solar radiation and regulating the planet's temperature. Earth's atmosphere also plays a crucial role in the water cycle, weather patterns, and climate regulation.

The surface of Earth is divided into several major landmasses, including continents and islands, which are surrounded by vast oceans. These landmasses are constantly shifting and changing due to processes like plate tectonics and erosion, shaping the planet's landscape over millions of years.

Earth is also home to a staggering array of life forms, from microscopic bacteria to towering trees and majestic animals. The diversity of life on Earth is unparalleled, with millions of species inhabiting every corner of the planet, from the depths of the ocean to the highest mountains.

In addition to its natural beauty and biodiversity, Earth is also unique in its ability to sustain life. The presence of liquid water, moderate temperatures, and a stable atmosphere make Earth the perfect habitat for a wide variety of organisms, including humans. Protecting and preserving Earth's delicate balance is essential for the continued survival of life on our planet.

The Moon

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The Moon, Earth's only natural satellite, is a fascinating and mysterious world that has captivated humans for thousands of years. It orbits around Earth at a distance of about 238,855 miles (384,400 kilometers) and is about one-quarter the size of Earth. The Moon has a rocky surface covered in craters, mountains, and plains, with no atmosphere to protect it from meteoroids and solar radiation.

One of the most striking features of the Moon is its phases, which change as it orbits around Earth. These phases, from a full moon to a new moon and back again, are caused by the relative positions of the Moon, Earth, and Sun. The Moon's gravity also affects Earth's tides, causing them to rise and fall in a predictable pattern.

The Moon has played a crucial role in human history and culture, inspiring myths, legends, and scientific inquiry. It has been the target of numerous spacecraft and missions, including the Apollo missions, which brought humans to the lunar surface for the first time. Today, the Moon continues to be a focus of scientific research and exploration, with plans for future missions to return humans to the lunar surface and establish a permanent presence there.

Mars

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Mars, often called the "Red Planet" due to its rusty hue, is a cold and barren world with a fascinating history. It is the fourth planet from the Sun and is about half the size of Earth. Mars has intrigued scientists for centuries with its potential for harboring life and its similarities to Earth.

The surface of Mars is covered in reddish-brown soil and is dotted with impact craters, volcanoes, and vast plains. One of the most prominent features of Mars is Olympus Mons, the largest volcano in the solar system, which stands nearly three times taller than Mount Everest. Mars also has a massive canyon system called Valles Marineris, which stretches for over 2,500 miles (4,000 kilometers) and is deeper than the Grand Canyon.

Despite its barren appearance, Mars has captured the imagination of scientists and explorers alike. Evidence from spacecraft and rovers suggests that Mars was once a warmer and wetter planet with rivers, lakes, and possibly even oceans. Scientists continue to search for signs of past or present life on Mars, studying its geology, atmosphere, and climate to unravel the planet's mysteries.

In recent years, Mars has become a focus of human exploration, with numerous missions planned to study the planet and prepare for future human missions. NASA's Perseverance rover, launched in 2020, is currently exploring the surface of Mars, searching for signs of ancient microbial life and collecting samples for return to Earth. The exploration of Mars holds the promise of answering fundamental questions about the potential for life beyond Earth and the future of human space exploration.

Jupiter

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Jupiter, the largest planet in our solar system, is a gas giant with a mesmerizing appearance and a host of fascinating features. It is the fifth planet from the Sun and is more than twice as massive as all the other planets combined. Jupiter's massive size and strong gravitational pull make it a dominant force in the solar system, influencing the orbits of nearby objects and protecting the inner planets from potential impacts.

One of the most striking features of Jupiter is its colorful bands of clouds, which are made up of ammonia crystals and other compounds. These bands of clouds swirl around the planet, creating mesmerizing patterns and storms that can last for centuries. The most famous of these storms is the Great Red Spot, a massive storm system that has been raging for over 300 years and is larger than Earth itself.

Beneath its thick atmosphere, Jupiter has a core made of rock and metal surrounded by layers of hydrogen and helium gas. Despite its massive size, Jupiter has no solid surface, so if you were to try to land on the planet, you would simply fall through its atmosphere until you reached its core.

Jupiter is also home to a diverse array of moons, with over 70 known moons orbiting the planet. The four largest moons – Io, Europa, Ganymede, and Callisto – are known as the Galilean moons and were discovered by the astronomer Galileo Galilei in 1610. These moons are each unique worlds with their own geology and atmosphere, and they continue to fascinate scientists with their potential for harboring life.

Saturn

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Saturn, known for its majestic rings, is the sixth planet from the Sun and the second largest in our solar system. It is a gas giant like Jupiter, composed mostly of hydrogen and helium, with a small rocky core at its center. Saturn's most distinctive feature is its rings, which are made up of billions of icy particles ranging in size from tiny grains to large chunks. These rings extend thousands of kilometers from the planet's surface and are visible even from Earth with a small telescope.

Beneath its rings, Saturn has a thick atmosphere with colorful bands of clouds, similar to Jupiter. The planet's atmosphere is primarily composed of hydrogen and helium, with traces of other gases like methane and ammonia. Saturn's atmosphere is also home to powerful storms, including a hexagonal-shaped storm near its north pole.

Saturn has a diverse collection of moons, with over 80 known moons orbiting the planet. The largest of these moons is Titan, which is larger than the planet Mercury and is the only moon in the solar system with a dense atmosphere. Titan's atmosphere is primarily composed of nitrogen, with traces of methane and other gases, making it an intriguing target for future exploration.

In addition to Titan, Saturn's moons include Enceladus, which has geysers of water vapor erupting from its surface, and Mimas, which has a large crater resembling the "Death Star" from Star Wars. These moons, along with Saturn's rings, make it one of the most captivating objects in the night sky.

Uranus

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Uranus, the seventh planet from the Sun, is an ice giant with a mysterious and enigmatic atmosphere. It is the third largest planet in our solar system and is tilted on its side, with its axis of rotation nearly parallel to its orbit around the Sun. This unique orientation gives Uranus its distinctive appearance and causes extreme seasonal variations as it orbits the Sun.

Uranus has a thick atmosphere composed primarily of hydrogen and helium, with traces of methane that give it a blue-green color. The planet's atmosphere is marked by high-speed winds that can reach speeds of up to 560 miles per hour (900 kilometers per hour). Uranus also has a system of faint rings and a collection of moons, the largest of which is named Titania.

Despite its unique features, Uranus is one of the least explored planets in our solar system, with only one spacecraft – Voyager 2 – having visited the planet in 1986. The limited data collected by Voyager 2 has left many questions unanswered, including the origin of Uranus' unusual tilt and the composition of its atmosphere. Future missions to Uranus could provide valuable insights into the history and evolution of our solar system.

Neptune

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Neptune, the eighth and farthest planet from the Sun, is a frigid and distant world with a dynamic and turbulent atmosphere. It is the fourth largest planet in our solar system and is composed primarily of hydrogen and helium, with traces of methane that give it a blue color. Neptune's atmosphere is marked by powerful storms, including the Great Dark Spot – a massive storm system similar to Jupiter's Great Red Spot.

Neptune has a system of faint rings and a collection of moons, the largest of which is named Triton. Triton is unique among Neptune's moons because it orbits the planet in a retrograde direction, opposite to the planet's rotation. Triton is also one of the coldest objects in our solar system, with surface temperatures that can plunge to minus 391 degrees Fahrenheit (minus 235 degrees Celsius).

Despite its remote location, Neptune has been visited by only one spacecraft – Voyager 2 – which flew by the planet in 1989. Voyager 2 provided valuable data about Neptune's atmosphere, rings, and moons, but many questions remain unanswered. Future missions to Neptune could provide insights into the planet's composition, weather patterns, and geological features.

The Milky Way

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The Milky Way, our home galaxy, is a vast and majestic cosmic structure that stretches across the night sky like a shimmering river of stars. Named for its hazy appearance as seen from Earth, the Milky Way is a spiral galaxy composed of billions of stars, stellar remnants, gas, and dust, bound together by gravity.

At the heart of the Milky Way lies a dense region known as the galactic bulge, where stars are densely packed and stellar densities are highest. Surrounding the bulge is a flattened disk of stars, gas, and dust, which extends outward in a spiral pattern. Spiralling arms of stars and interstellar material spiral outwards from the central bulge, creating the iconic spiral arms that give the galaxy its distinctive appearance.

Our solar system resides in one of the Milky Way's spiral arms, known as the Orion Arm or Local Spur. From our vantage point within the galaxy, we peer outward into the vast expanse of space, observing the stars, nebulae, and other celestial objects that populate our cosmic neighbourhood.

The Milky Way is a dynamic and evolving entity, with stars orbiting the galactic centre in elliptical, circular, and spiral trajectories. Over billions of years, these stars interact with one another, forming stellar clusters, binary systems, and occasionally, catastrophic events such as supernovae and black hole mergers.

Moreover, the Milky Way is not alone in the cosmos but is part of a larger cosmic web of galaxies, clusters, and superclusters, bound together by the force of gravity. As we peer deeper into space with telescopes and observatories, we uncover the vastness of the universe and our place within it.

Studying the Milky Way provides insights into the formation, evolution, and dynamics of galaxies, shedding light on the processes that shape the cosmos. It allows us to probe the mysteries of dark matter and dark energy, understand the origins of stars and planets, and explore the potential for life beyond Earth.

Our Galaxy

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Our galaxy, known as the Milky Way, is a spectacular celestial phenomenon that enchants observers with its vastness and beauty. It spans an immense distance of about 100,000 light-years and comprises billions of stars, along with interstellar gas and dust. A stunning spiral galaxy, the Milky Way boasts a mesmerising structure, with a central bulge surrounded by a flattened disk of stars, gas, and dust. Radiating outwards from the bulge are magnificent spiral arms, each adorned with stellar clusters, nebulae, and other celestial wonders.

Nestled within one of these spiral arms, our solar system finds its home. From our position within the galaxy, we are afforded a breathtaking view of the cosmos, as we peer into the depths of space and marvel at the myriad stars and galaxies that populate our galactic neighbourhood.

The Milky Way is a dynamic and ever-evolving entity, with stars tracing graceful orbits around its centre. Over eons of time, these stars interact, forming clusters, binary systems, and occasionally experiencing cataclysmic events such as supernovae and black hole mergers.

Furthermore, the Milky Way is not an isolated entity but rather part of a vast cosmic ensemble, bound together by the force of gravity. As we explore the universe with increasingly powerful telescopes and instruments, we gain insights into the interconnectedness of galaxies and the intricate tapestry of the cosmos.

Studying our galaxy opens a window into the mysteries of the universe, offering clues about its origins, evolution, and ultimate fate. It allows us to ponder the enigmatic phenomena of dark matter and dark energy, contemplate the formation of stars and planets, and speculate about the possibility of life beyond our solar system.

In conclusion, the Milky Way stands as a testament to the grandeur and complexity of the universe, inspiring wonder and curiosity in all who contemplate its splendour. By studying our galaxy, we embark on a journey of discovery, deepening our understanding of the cosmos and our place within it.

The Sun

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The Sun is the star at the centre of our Solar System. It is by far the most important source of energy for life on Earth. The interactions between the Sun and Earth drive the seasons, ocean currents, weather, climate and calendar.

The Sun is 75% hydrogen and 25% helium. It’s energy comes from the fusion of hydrogen into helium. Its diameter is about 1.39 million kilometres (864 000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth.

The Sun currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second producing light and heat. It takes light just over 8 minutes to travel the 150 000 000 km (93 000 000 miles) from sun to earth. Of the approximately 1 500 W/m2 of energy that reaches earth only 1 000 W/m2 reaches the ground.

Our sun’s class and size make it a yellow dwarf star. It formed approximately 4.6 billion years ago. It accounts for about 99.86% of the total mass of our solar system. The rest flattened into an orbiting disk from which the planets formed. The sun’s gravity holds our solar system together, keeping everything from the biggest planets to the smallest particles of debris in its orbit.

Electric currents in the Sun generate a magnetic field that is carried out through the solar system by the solar wind—a stream of electrically charged gas blowing outward from the Sun in all directions.

There are billions of stars like our Sun in just our Milky Way galaxy alone.