History of Marine Sciences
& Ocean Discovery
Marine science didn't start with Captain Cook. It started 150 000 years ago on the South African coast, with people who left no books — but did leave dinner. The story of how humans came to understand the ocean runs from those shell-piles in caves above the surf, all the way to the satellites and ROVs of today. Your generation writes the next chapter.
Long before any European "discovered" the SA coast, people were studying it. Not with notebooks — with dinner. There are caves at Mossel Bay where the rubbish from 150 000 years of beach meals is piled metres deep. What can a stack of old shells teach scientists today?
Almost everything. Climate, sea level, which species lived where, how harvesting changed over time, even what people chose not to eat. The piles are called middens — datable layers of food waste. Archaeologists like UCT's Prof. John Parkington spend their careers reading them, and they tell tens of thousands of years of human-ocean history with extraordinary precision.
Marine science didn't start with the Royal Navy. It started with the first person who stood at the tide line and asked when's it coming back? — and got useful enough at predicting it to feed a whole community. This topic is the long, weird, and complicated story of how we got from there to here.
Knowledge of the Sea is Older Than Writing
Three threads run through the history of marine science.
First: indigenous and applied knowledge — coastal peoples observing, predicting, and using the ocean for tens of thousands of years. Strandlopers in southern Africa, Polynesian wayfinders, the fishing communities of the Mediterranean. They didn't publish, but they got it right enough to survive.
Second: recorded science — Greek scholars writing it down, Arabic and Chinese astronomers refining navigation, European naturalists collecting specimens, the HMS Challenger founding modern oceanography in the 1870s. Every modern textbook is built on this layer.
Third — and this is uncomfortable — colonialism and conquest. A lot of what's recorded as "discovery" was invasion. The same voyages that mapped currents and catalogued species also took land and people by force. A good marine scientist learns the science and the context.
The Long Arc
Tap any point on the timeline below to read what happened, who was involved, and why it mattered for marine science. The dates are not to scale — 150 000 years doesn't fit on one page.
Local connection — Pinnacle Point and the longest record on Earth
The caves at Pinnacle Point near Mossel Bay, just 200 km up the coast from Gqeberha, hold one of the oldest records of human marine harvesting anywhere — over 160 000 years deep. What people ate, when they ate it, and how the climate around them was shifting at the time. South Africa is unusual: huge stretches of our coast were continuously inhabited through ice ages and warm periods. That's why the SA coastal record is so valuable to global marine science. The "start" of marine science isn't a Greek philosopher or a British captain — it's people standing on rocks at low tide, just down the road from where you live.
How Do You Actually Get a Sample?
This is CAPS's first key concept for the block, and it is the half of the history that gets skipped. Every fact about the deep sea had to be fetched — from kilometres down, from a moving ship, with the technology of the day. The story of marine science is largely the story of the tools.
Where it starts: wax on a weight and line
The first technique CAPS names, and the crudest. A weighted rope was lowered over the side until it hit bottom, and the length paid out gave the depth. To find out what the bottom was made of, sailors stuck wax onto the weight — grains of sand and sediment pressed into it on impact and came up stuck to the wax.
It was a clumsy method, and the reasons matter more than the method:
- The rope stretched under its own weight, so the length paid out was longer than the true depth — every reading was an over-estimate.
- Currents dragged the line sideways, so it was not even measuring straight down.
- The sediment sample was tiny — whatever would stick to a lump of wax.
The fix was not a new idea, it was a new material: piano wire replaced the rope, because it does not stretch. Depth readings became far more accurate overnight. 📌 That is the pattern for this whole section — a limitation in the tool, then a material or a machine that removes it. You will re-enact this yourself in the practical.
| Tool | When | What it collects | Its limitation |
|---|---|---|---|
| Wax on a weight and line | Early | Depth, and a few grains of sea-floor sediment | Rope stretches; currents drag it; sample tiny |
| Piano wire | Later 1800s | The same, far more accurately | Still one point at a time, still slow |
| Steam winch and dredger (Challenger) | 1872–76 | Thousands of sediment and water samples, plus temperature, pressure at depth, tides, waves and currents | Needs a ship, a crew and years at sea |
| Nansen bottle | 1894 | A water sample from a chosen depth | One bottle, one depth, per lowering |
| Niskin bottle | 1966 | The same idea, improved — and mountable in a rosette of many bottles | Still discrete samples, not a continuous record |
| CTD | Modern | Conductivity (which gives salinity), Temperature and Depth, recorded continuously as it descends | Measures the water; still needs bottles to bring any of it back |
| Sonar | 1910s–20s | Depth along a continuous track — this is what mapped the sea floor | Tells you shape, not composition |
| Satellite imaging | 1970s onward | Sea-surface height, temperature and colour, globally and repeatedly | Sees the surface only |
| Scuba, submersibles, ROVs, gliders | 1943 onward | A human or a robot actually there, choosing what to pick up | Expensive; depth-limited for humans |
Two things that pushed this forward, and neither was curiosity
War. The World Wars led European governments to compete for dominance of "ocean territory", and funds were directed at instruments that recorded ocean information accurately. Sonar, developed to map the sea floor, is the example the source gives. After the Second World War scientists from different nations began cooperating instead, which is where multinational marine science projects come from.
Access. Scuba equipment and submersible craft made areas of the ocean accessible to humans that simply were not before. That is a different kind of advance from a better instrument: it is the difference between sampling a place and being there. Sonar told us the sea floor had mountains; a submersible let someone look at one.
The Fish That Was Supposed to Be Extinct
CAPS names four South Africans for this block. This is the one with the best story, and it happened on our coast, in East London — about two and a half hours from Gqeberha.
December 1938 — the catch
Marjorie Courtenay-Latimer, the young curator of the East London Museum, went down to the docks to look over a trawler's catch, as she often did. Among it was a fish she did not recognise: about 1.5 m long, steel blue, with heavy scales and — the strange part — fins on fleshy, limb-like stalks. She could not preserve it properly, so she sketched it and wrote to the one person she thought might know.
The identification
Professor J.L.B. Smith, a chemistry lecturer at Rhodes University and a self-taught ichthyologist, saw the sketch and did not believe it. When he finally reached East London he did: it was a coelacanth, a lobe-finned fish known only from fossils and thought to have died out with the dinosaurs, roughly 66 million years earlier. He named it Latimeria chalumnae — for Latimer, and for the Chalumna River off which it was trawled.
The fourteen-year wait
The soft internal parts had been thrown away before Smith arrived, so the single most important question — how is it built inside? — could not be answered. Smith spent fourteen years hunting a second specimen, offering rewards along the East African coast. One finally turned up in 1952, in the Comoros. The SA Prime Minister authorised a military aircraft to fetch it.
Why it mattered — and what it did not prove
Coelacanths are lobe-finned fish: their fins sit on muscular, limb-like lobes rather than attaching straight to the body. That group is close to the ancestry of every four-limbed animal on land, including you. Having a living one to study, rather than a flattened fossil, was extraordinary.
But be careful with the popular version. A living coelacanth does not mean the species stopped evolving, and it is not "our ancestor" — it is a surviving cousin of the lineage that led to land animals. What the discovery really proved is smaller and more useful: "absent from the fossil record" is not the same as "extinct". A gap in the evidence is a gap in the evidence.
📌 That is the same lesson as the errors-in-thinking grid below — and it is exactly the reasoning Topic 5 is training you in.
Local connection — and they are still here
Coelacanths were found again in 2000 at Sodwana Bay, in the submarine canyons off KwaZulu-Natal — the same submarine canyons you met in Topic 3, in the Delagoa and Natal biogeographic zones from Topic 2. They live at around 100–150 m, in caves, and come out at night. South Africa is one of very few countries with a living coelacanth population, and the institute that carries Smith's collection — now SAIAB in Makhanda — is an hour and a half up the road.
South Africa's Marine Sciences Story
Gilchrist did not appear from nowhere. John Murray, who had sailed on the Challenger, recommended to the South African Department of Agriculture that it appoint a scientist in Cape Town to research the fisheries off the Cape coast. That recommendation is why John Gilchrist was appointed in 1895 — so the Challenger expedition and South African marine science are directly connected, not two separate stories.
A Scottish-built trawler was bought and renamed the Pieter Faure to run those trawls. Gilchrist spent thirty years building the foundation: the survey work that found the hake fishery, the country's first public aquarium at St James, and the Zoology department at UCT.
The ships, as one line: Pieter Faure → SA Agulhas II
CAPS asks for the arc, not the endpoints. It runs from a second-hand Scottish trawler in 1895, working a few days' steam from Cape Town, to the SA Agulhas II — a modern polar research and supply vessel that can break ice, carry laboratories and helicopters, and keep scientists working safely in the Southern Ocean. Same purpose, 120 years apart: put people and instruments where the questions are.
⚠️ Date to treat with care: the source supports St James as the first public aquarium in South Africa but gives no year. The 1903 below is likely close but is not source-verified, unlike every other date on this row. Check it before quoting it in an exam.
Errors in thinking — then and now
Every era of marine science had wrong ideas that everyone believed. The point of studying history isn't to laugh at them — it's to spot the same mistakes when we make them today.
Then — confidently wrong
- The sea boils beyond the equator — therefore no sailing south of the tropics.
- Ships fall off the edge of the Earth past a certain longitude.
- Sea monsters and vortexes lurk beyond known waters.
- Edward Forbes insisted no life existed below 545 m. Wrong by ~10 km.
- The seafloor is flat and featureless. (See Topic 3.)
- Ocean currents only exist in rivers — that's why the Greeks named the Atlantic Okeanos: "the great river".
Now — same trap, new dressing
- A scientist funded by a fishing company under-reports overfishing because the funder doesn't want to see it.
- A climatologist funded by an oil company under-reports the link between fossil fuels and warming.
- A researcher hides a result that would upset a high-profile collaborator.
- A whole field gets stuck on a popular but wrong idea because nobody wants to be the one to challenge a famous professor.
- "Tell the funder what they want to hear" is the same trap European navigators fell into reporting back to the Crown.
This is exactly why Topic 5 matters
The scientific method — observe, question, hypothesise, design, conduct, analyse, communicate — is the rulebook for not being confidently wrong. Every step is a guard against bias and groupthink. Repeatable, transparent, testable. That's the difference between knowledge and folklore. The scientists you respect most are the ones who report results even when their funder hates them.
And You — What the Job Actually Is
CAPS's Depth column for this block does not stop at history. It says the history of marine science discovery "should encourage learners to make a contribution themselves in the future." So: what does the contribution look like?
What a marine scientist does most days
Far less swimming than you would think. Most of the work is collecting samples on a schedule, processing them, and arguing with the numbers — the same loop from Topic 5. Fieldwork is intense and occasional; the analysis is constant. The people who last are the ones who like the data, not just the sea.
What the SA Agulhas II carries
Wet and dry laboratories, winches for CTD rosettes and nets, echo-sounders, a moon pool, helicopters, and berths for scientists as well as crew. It runs the SANAE Antarctic relief voyage and doubles as a floating research station — which is why a berth on it is one of the things South African marine scientists compete for.
Where you would study it
Marine science degrees in South Africa run through universities on and near the coast, and research sits in bodies such as SAIAB (Makhanda), SAAMBR/ORI (Durban) and DFFE. Maths and Physical Sciences to matric are the entry requirement — see Topic 1.
An argument worth having — Branch & Branch on limpets
CAPS's Resources column names George Branch, Living Shores of Southern Africa, and the argument it is best known for is a genuinely hard one. People have harvested shellfish off these shores for tens of thousands of years — Parkington's work in Section 1 is exactly that record. So when does harvesting become over-exploitation?
The uncomfortable version of the question: the archaeological record suggests that when people had sheep, they ate fewer limpets — so keeping livestock may have protected the shore. Which means the answer to "how do we protect marine resources?" might sometimes be "give people something else to eat", not "ban them from the shore". Hold both halves before you decide.
In the Lab — the CAPS Investigations
CAPS asks for a museum or DFFE warehouse visit to see the SA Agulhas, and a talk by a scientist showing the different equipment. Neither is something you can arrange this afternoon — so the practical sheet carries both as structured worksheets with the visit and the talk supplied in described form, and adds the one piece of this block you can genuinely do with your hands.
- 🟡 string + weight Re-enact "wax on a weight and line". Sound a depth, bring up a sediment sample on press-stick, and then measure how wrong you were — and in which direction.
- 🟢 desk The sampling ladder. Given one patch of sea floor, work out what each tool from wax to satellite would and would not tell you about it.
- 🟢 desk JLB Smith and the coelacanth — the discovery, and the reasoning question underneath it.
- 🏛️ visit 🟢 desk The museum visit and the scientist's talk — CAPS's own two investigations, with described versions supplied so neither is blocked.
→ Open the Topic 8 practical sheet — printable, with supplied data for every task.
Key Vocabulary
Tap each card to flip it. These eight terms are examinable.
Beach-dwelling hunter-gatherer communities of southern Africa. Lived along the coast for over 150 000 years, harvesting molluscs, fish and beached marine mammals, and leaving the world's oldest sustained record of human-ocean interaction.
Ancient shell-and-bone rubbish piles left by coastal communities. Layered like cake — archaeologists date each layer and read climate, diet and harvesting practices from it.
The person responsible for working out where a ship is and where it should go next. Skill exploded once accurate timekeepers (John Harrison's H4, 1761) made longitude measurable at sea.
Specialised maps showing coastlines, depths, currents and hazards. Captain James Cook's Pacific charts were so accurate they were still used for navigation in WWII.
One nation extending military, political and economic control over another. The European voyages of "discovery" were also voyages of imperialism — claim land, extract resources, expand the home economy.
The policy of economically controlling a foreign nation, its people and territory. A specific form of imperialism. Marine science as a discipline grew up entangled with it; modern marine science is still untangling.
A scientist who names, defines and classifies living organisms. Carl Linnaeus — the founder — described many of the first SA marine specimens after a three-year stay in Cape Town.
Anything attached to or living near the seabed. Gilchrist's big ambition was to catalogue the benthic fauna of the entire SA coast — sole, hake, urchins, worms, the lot.
A lobe-finned fish known only from fossils and thought extinct for ~66 million years, until one was trawled off East London in 1938. Named Latimeria chalumnae. Still living off Sodwana Bay today.
Conductivity, Temperature, Depth. An instrument lowered through the water column that records all three continuously as it descends. Conductivity is how salinity is measured. Usually mounted in a rosette with Niskin bottles.
Sending a pulse of sound to the sea floor and timing the echo back. Developed in the early 20th century, largely driven by war. It is what mapped the sea floor — and what overturned the belief that the sea floor was flat.
A small crewed craft built to work at depth. With scuba (1943) it changed marine science from sampling a place to being there — CAPS's point that these technologies made areas of the ocean accessible to humans. Robotic versions are ROVs.
A net or frame dragged along the sea floor to collect sediment and bottom-dwelling organisms. The Challenger's steam-powered winch drove one, and it is how thousands of samples — and 4 717 new species — were collected.
Quick Check
Question 1
Well done!
Move on to Topic 9 when you're ready.