Oxford University Museum of Natural History
Oxford University Museum of Natural History
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Allan Savory v George Monbiot debate | Is livestock grazing essential to mitigating climate change?
In the holistic planned grazing process, livestock are used as a tool to reverse the biodiversity loss that leads to desertification - a major contributor to climate change. Yet critics argue that livestock grazing, in almost all circumstances, is a net contributor to climate warming.
On 11 July 2023, founder and proponent of Holistic Management Allan Savory met prominent critic George Monbiot at Oxford University Museum of Natural History for a debate chaired by Dame Professor E.J. Milner-Gulland.
About Allan Savory:
Allan Savory began his career in the 1950s as a research biologist in central Africa where the loss of biodiversity in game reserves and national parks alarmed him. Reversing it became his life's focus and led to a significant breakthrough that became known in 1984 as Holistic Management. He is the author of Holistic Management: A Commonsense Revolution to Restore Our Environment, Third Edition (Island Press, 2016), and numerous scholarly papers and articles. He has been honoured by The Weston A. Price Foundation (Integrity in Science), the Buckminister Fuller Institute (for his work's "significant potential to solve some of humanity's most pressing problems") and the Banksia Foundation Australia (for "the person doing the most for the environment on a global scale"). He is President of the Savory Institute.
About George Monbiot:
George Monbiot is an author, Guardian columnist, and environmental activist whose current research focus is on the global food system. His best-selling books include Feral: Rewilding the land, sea, and human life, Heat: How to stop the planet burning, and Out of the Wreckage: a new politics for an age of crisis. George was awarded the Orwell Prize for Journalism in 2022. In the same year, he became an Honorary Fellow of Wolfson College, Oxford. George's latest book, Regenesis: Feeding the World without Devouring the Planet (shortlisted for the James Cropper Wainwright Prize for Writing on Conservation) draws on astonishing advances in soil and ecology to explore pioneering ways to grow more food with less farming.
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OXFORD UNIVERSITY MUSEUM OF NATURAL HISTORY
Oxford University Museum of Natural History was established in 1860 to draw together scientific studies from across the University of Oxford. Today, the award-winning Museum continues to be a place of scientific research, collecting and fieldwork, and plays host to a programme of events, exhibitions and activities for the public and school students of all ages.
Follow us on social media ► @morethanadodo
Website ► oumnh.web.ox.ac.uk/
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LEVERHULME CENTRE FOR NATURE RECOVERY
The Leverhulme Centre for Nature Recovery acts as a hub for innovative thinking, discussion and analysis of nature recovery nationally and worldwide, it unites leading researchers from a wide range of disciplines across Oxford University, its interdisciplinary approach bringing together expertise from the departments of geography, ecology, social science, finance, economics, psychiatry, anthropology, artificial intelligence, statistics and earth observation, to collaborate on a range of projects, in conjunction with national and international partners.
Follow us on social media ► @NatureRecovery
Website ►www.naturerecovery.ox.ac.uk/
Переглядів: 62 592

Відео

Discover the Museum of Natural History
Переглядів 28 тис.Рік тому
Explore the Museum of Natural History, home to Earth, science and nature. For cappuccinos to dinosaurs, the Museum is free and open daily. Find out more and plan your visit at www.oumnh.ox.ac.uk
Drawn to Nature: Conservation
Переглядів 8942 роки тому
Join our Life conservationist Jackie Chapman-Gray as she discusses her role in the Museum and shares a few of her favourite specimens for you to draw.
Hippos in Britain -- Part 3 Our Oldest Hippo
Переглядів 9642 роки тому
Oxford University Museum of Natural History project officer Neil Adams has recently discovered the oldest known hippo fossil from Britain. He shares some of the earliest hippos to arrive in Europe, as well as his exciting new find.
Hippos in Britain -- Part 2: Hippos By The Sea
Переглядів 7572 роки тому
Travel with Project Officer Neil Adams to the East Anglian coastline to talk about seaside British hippos.
Hippos in Britain -- Part 1: Common As Muck
Переглядів 1,1 тис.2 роки тому
Learn from the Museum's pleistocene Project Officer, Neil Adams, about an animal that used to be widespread across Britain: the hippopotamus.
How can we predict species decline as a result of threats like agriculture?
Переглядів 5282 роки тому
Produced as part of the Meat the Future exhibition at Oxford University Museum of Natural History: www.oumnh.ox.ac.uk/meat-the-future
Drawn to Nature: Beetles
Переглядів 1,2 тис.3 роки тому
In a year where people have found increasing solace in, and drawn creative inspiration from the natural world, we invite you to participate in and enjoy Drawn to Nature: Insects. Join Museum Collections Assistant, Rob Douglas, to hear about the natural history and conservation status of some of the planet’s most varied and important creatures, the insects, before taking a chance to draw your ow...
Meat: The Future?
Переглядів 6673 роки тому
Across the world, ninety per cent of people are meat-eaters and global consumption is rising. New research from the LEAP (Livestock Environment and People) project at the University of Oxford has revealed the cost to us and the planet of keeping so much meat on the menu. Join Professor Susan Jebb and Professor Sir Charles Godfray for the 'Meat The Future' exhibition launch event, chaired by jou...
Drawn to Nature: Minerals
Переглядів 9833 роки тому
From a relatively modest toolkit of chemical elements, an amazing range of minerals with different crystal shapes, colours and properties can be found. Join Museum Collections Manager, Dr Duncan Murdock, to hear about the what the geometry of crystals can reveal about the rocks and minerals they’re contained in. Dr Duncan Murdock is a Collections Manager in Earth Collections, and is responsible...
Angela Palmer: '2020' at Oxford University Museum of Natural History
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Angela Palmer: '2020' at Oxford University Museum of Natural History
Drawn to Nature: Birds
Переглядів 5933 роки тому
Drawn to Nature: Birds
Saving our Insects with Dave Goulson
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Saving our Insects with Dave Goulson
Visit the Oxford University Museum of Natural History
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Visit the Oxford University Museum of Natural History
Drawn to Nature: Rock Pools
Переглядів 7943 роки тому
Drawn to Nature: Rock Pools
How to Save the Earth in Four Steps with Henry Grub
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How to Save the Earth in Four Steps with Henry Grub
Drawn to Nature: Decorating a Museum
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Drawn to Nature: Decorating a Museum
Science Short: Food and Social Networks
Переглядів 3423 роки тому
Science Short: Food and Social Networks
Drawn to Nature: Amber
Переглядів 1,7 тис.3 роки тому
Drawn to Nature: Amber
Drawn to Nature: Plesiosaurs
Переглядів 2,9 тис.3 роки тому
Drawn to Nature: Plesiosaurs
Wildlife, Warriors and Women
Переглядів 6143 роки тому
Wildlife, Warriors and Women
Drawn to Nature: Nautilus
Переглядів 1,5 тис.3 роки тому
Drawn to Nature: Nautilus
Metabolism of Planet Earth
Переглядів 8 тис.3 роки тому
Metabolism of Planet Earth
Drawn to Nature: Flies
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Drawn to Nature: Flies
3DVis Session 2: 3D Visualization in the Natural Sciences
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3DVis Session 2: 3D Visualization in the Natural Sciences
3DVis Session 1: 3D Visualization in the Humanities
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3DVis Session 1: 3D Visualization in the Humanities
3DVis Session 3: 3D Visualization and Industry
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3DVis Session 3: 3D Visualization and Industry
3DVis Session 4: The Future of 3D Visualization in Cultural Heritage
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3DVis Session 4: The Future of 3D Visualization in Cultural Heritage
Fungal Catastrophes with Professor Mat Fisher
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Fungal Catastrophes with Professor Mat Fisher
Mystery at the Museum with Steve Backshall - Trailer 4
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Mystery at the Museum with Steve Backshall - Trailer 4

КОМЕНТАРІ

  • @dudotolivier6363
    @dudotolivier6363 6 днів тому

    This video depict a reconstruction of the Maotianshan Shales (帽天山页岩) formation. One of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue species, comparable to the fossils of the Burgess Shale of British Columbia, Canada (one of the main Cambrian aged formations in term of exceptionnal high quality preservation and diveristy). A formation as rich in shelled arthropods species as soft-bodies species, while the second category of animals geenrally do'nt tend to even fossilized in the fossils records (because not having shell nor bones as remains which can fossilized).

  • @jacobturner3059
    @jacobturner3059 7 днів тому

    I jumped when the anomalocaris came on screen near the end.

  • @jamesspry3294
    @jamesspry3294 13 днів тому

    I don't care what Monbiot says, I just know that on my little farm, the carbon is going into the soil and the biodiversity is increasing. I use grazing animals using the holistic management framework that Alan (et al) developed. It works. I've seen it on my place.

  • @jonathanroberts-bj7yl
    @jonathanroberts-bj7yl 15 днів тому

    Any Crocodiles?

  • @RS-ln3ns
    @RS-ln3ns 19 днів тому

    ANOTHER AMERICAN VIDEO, SHOWING FALSE BS INFORMATION ABOUT BRITAIN.

  • @andytrommald5327
    @andytrommald5327 22 дні тому

    I fully agree with Alan's work and believe his holistic method can save our deserts but he's such a weak debater I'm beating myself up listening to him

  • @Cons408
    @Cons408 23 дні тому

    The likes are 666😰

  • @cornelia3130
    @cornelia3130 24 дні тому

    I love this Cambrian world asmr 😍

  • @prettynoose888
    @prettynoose888 25 днів тому

    So this Allen Savory shot 40 000 elephants, what a despicable human, how can he even show his face in public. He should be locked up away!!!

  • @joedusel
    @joedusel 27 днів тому

    LOL, logic versus gibberish. That was a debate?

  • @pedrovanius2025
    @pedrovanius2025 28 днів тому

    🇧🇷🤙🏻

  • @perjalananwaktu7181
    @perjalananwaktu7181 29 днів тому

    Why they didn't just clone the dead one and forget about extinction

  • @DebacleUK
    @DebacleUK Місяць тому

    shot 40,000 elephants - and you were WRONG

  • @GrowYourOwnLife
    @GrowYourOwnLife Місяць тому

    GM not coming across well. Alot of bluster & aggression without saying very much.

  • @tman250
    @tman250 Місяць тому

    Many comments here suggest that Allan Savory didn't address the debate's title, but he actually did. It's just that George Monbiot, most of the audience, and I (for a while) missed it. I thought it worthwhile to post this a few times in a few different areas of the comments section because Allen's arguments are worth understanding. The debate's title is "Is livestock grazing essential to mitigating climate change?" It is not about: * Will livestock grazing reduce global warming? * Will livestock grazing reduce atmospheric carbon? * Will livestock grazing reduce greenhouse gases? George Monbiot conflated climate change with global warming and increased atmospheric carbon. However, these are distinct concepts. We notice climate change through: * Greater temperature extremes in various places (e.g., shifting from very hot to very cold), making them hard to live in * More extreme weather events globally * The inability to farm due to these changes * Loss of coastal land from rising sea levels Scientists have found a correlation between increasing greenhouse gases and rising global temperatures, linking these temperatures to climate change. They thus conclude that reducing greenhouse gases is crucial for combating climate change, a view George Monbiot supports. Allan Savory, however, disagrees. He believes that combating desertification is the key to addressing climate change, reasoning that: * Deserts experience extreme temperature swings (very hot days and very cold nights), making them uninhabitable * Desertification alters local weather patterns (e.g., reducing rainfall and creating conditions for extreme weather elsewhere) * Desertification reduces an area's resilience to extreme weather (e.g., deserts flood while grasslands absorb water) * These factors make the land unfarmable Desertification doesn't directly impact rising sea levels, but it can be argued that the loss of farmable or habitable land poses a greater threat to humanity than the loss of some coastal areas. This is why Allan Savory says "forget carbon." To George Monbiot, this equates to "forget climate change," leading him to accuse Allan of not addressing the debate's title. However, Allan was always focused on the core issue. Allan is not a trained debater or academic. He approaches problems differently. If I were him, I would frame the debate as follows: "Desertification impacts climate change more than greenhouse gases, and livestock grazing is essential to stopping desertification." Allan would then support this statement, while George would argue against it. George would then have to admit that even with negative carbon emissions, we are in serious trouble if our land becomes desert. The world becomes unlivable, people can't feed themselves, and extreme weather events increase. In other words, climate change would still be rampant. Therefore, halting desertification must be prioritized over concerns about greenhouse gases. To Allan, the most effective way to combat climate change is to graze animals on borderline desert land using his grazing management techniques, transforming it into lush grassland. George can contest this only by: a) Providing evidence that Allan's grazing techniques do not stop desertification b) Demonstrating that rising greenhouse gases cause more desertification than improper grazing and farming practices Since George's debate focused on carbon sequestration, he couldn't directly challenge Allan's point. Instead, he led the audience to misunderstand Allan's argument. You'll notice Allan began by saying, "let's assume the soil captured zero carbon and that animals released 20 times the greenhouse gases they actually do." This was a significant clue that Allan was presenting a different perspective. If Allan were more articulate or if George were more balanced and less angry, making an effort to understand Allan's point, the debate could have been more productive.

    • @prettynoose888
      @prettynoose888 25 днів тому

      I do not care to understand a man who shot 40 000 elephants.

    • @tman250
      @tman250 25 днів тому

      @@prettynoose888 You miss the fact that he spent a significant portion of his life trying to remedy that mistake. People are capable of change and growth. I am sure you've made mistakes in the past that you've learned from. Suppose society decided to reject you based on your mistakes without considering that you've outgrown the mistake. You wouldn't feel great, and society would miss out on the good things you have to offer. I myself don't condone the act of farming animals for meat. All animal lives matter. But I can still appreciate Roger Savory's findings on how managed grazing can remove desertification and reduce climate change.

    • @prettynoose888
      @prettynoose888 24 дні тому

      @@tman250 Killing 40 000 elephants is unforgivable, it also proves he's NOT smart at all. There is nothing he can do to remedy that mistake. The thing is you (and most other humans) are anthropocentric and you see animals as mindless, unfeeling machines. You don't care about animals, nature or the planet and that is why you can so easily forgive the atrocities humans commit. Maybe you should watch channels like "HERD Elephant Orphanage South Africa" so that you can see how incredible elephants are, they are very complex, sensitive and emotional beings.

  • @MarieLotusBastard
    @MarieLotusBastard Місяць тому

    So siblings only have 50 percent shared DNA buteveryone shares DNA. That sounds like misrepresention and fraud. We are NOT ALL AFRICAN just because she is

  • @javiercarrera6092
    @javiercarrera6092 Місяць тому

    Savory is a practical land restoration expert who has helped regenerate thousands of acres and has taught his system to thousands of people. I have personaly witnessed the positive results of what he proposes. Monbiot is an intellectual with nothing to show.

  • @rossmcnally7016
    @rossmcnally7016 Місяць тому

    Savory managed to waste an hour and a half of everybody's time by refusing to engage with the terms of the debate which he himself had proposed. His only contribution was to pepper the discussion with a kind of grapeshot cannon of incoherent waffle about how the allies won the war by dealing with oxidation. By being as vague and obscurantist as possible, quacks like this are able to appeal to an audience who just read into their nonsense whatever they want to hear.

  • @pborogeopaleo
    @pborogeopaleo Місяць тому

    Excellent mini documentary, I'll have to ask the Peterborough Museum and Art Gallery if they would like to do one about the Plesiosaur I found from the same site a few years later. Which is now on permanent display in the Peterborough Museums marine reptile gallery 😊

  • @toni4729
    @toni4729 Місяць тому

    One point: Vegans graize. They never stop eating. Carnivores eat, (at most) twice a day.

  • @toni4729
    @toni4729 Місяць тому

    Climate change is caused mainly by plaughs and machinery on the land spraying toxins and collecting junk cereals by the millions of ton. Not cow burping.

  • @toni4729
    @toni4729 Місяць тому

    You lose George, you'll never turn the world vegan.

  • @toni4729
    @toni4729 Місяць тому

    We can't afford the water to grow the wheat and corn and grain and junk food that George want to feed us on.

  • @toni4729
    @toni4729 Місяць тому

    Well George, if you don't want to eat properly and let people bring up their children properly perhaps we should be stopped breeding like rabbits. We con't continue to explode out of control.

  • @toni4729
    @toni4729 Місяць тому

    This george guy wants to kill off all the animals (which will happen if he gets his way) and turn the world plastic.

  • @toni4729
    @toni4729 Місяць тому

    All you're doing with a plant based diet is growing plants with pesticides, herbicides and fungicides and I'm sure the chemical companies and oil companies love you sunshine.

  • @toni4729
    @toni4729 Місяць тому

    A plant based diet is suicide for the planet and the human race. YOU ARE NUTS.

  • @keeshea6718
    @keeshea6718 Місяць тому

    1:25:30 : and they say veganism is a religion :D .... how about being human/humane and show respect to the lives of the animals you kill needlessly

  • @keeshea6718
    @keeshea6718 Місяць тому

    he calls mass murdering 40'000 elephants a "blunder" !!

  • @margotbw4660
    @margotbw4660 Місяць тому

    Thank you for walking us through your methods and data! Really interesting studies!

  • @christophvonknobelsdorff1936
    @christophvonknobelsdorff1936 2 місяці тому

    film tear at the crucial point ? ...

  • @aelfricoxhey1191
    @aelfricoxhey1191 2 місяці тому

    Very poor debate. Old man waffling and an idiot displaying selective bias in the science that he quotes, yet claims to have read all the papers, obviously hasn't read any that I have.

  • @earthflute2248
    @earthflute2248 2 місяці тому

    George is the type of green ideolog who will only be happy when all animals roam free incl cats and dogs and ruminants are gone, we eat zee bugs and we are all sitting around fires coz the grid has collapsed under his green 'we are all going to die' utopia. Thank goodness there are practical people like Alan who ignore George's cherry-picked 'science'. Let George live his dream life alone and cold eating bugs. In a sterile environment destroyed by his pesticides herbicides and fertilisers. Not for me. Bring on the health giving red meat, proper sustainable farming and a happy bio environment.

  • @yummimuffuun6496
    @yummimuffuun6496 2 місяці тому

    Anyone come from Helldivers 2?

  • @wozzaladers3244
    @wozzaladers3244 2 місяці тому

    'All policy is created to meet a need a desire or address a problem!' ????????????? WTF

  • @wozzaladers3244
    @wozzaladers3244 2 місяці тому

    ua-cam.com/video/nub7pToY3jU/v-deo.html

  • @wozzaladers3244
    @wozzaladers3244 2 місяці тому

    Allan Savory doesn't explain HOW cattle remove carbon from the atmosphere and store it, he doesn't explain what process he used from the military to reduce carbon in the atmosphere, with respect he doesn't really make an argument at all? George Monbiot explained in reasonable and accessible detail how and why livestock and grassing are releasing more carbon to the atmosphere. After listening to this debate with an open mind, I am now more certain than ever that live stock agriculture must change if we are to save our environment from further disaster!

  • @marlan5470
    @marlan5470 2 місяці тому

    1- Most of the corn now goes into ethanol. Management of pastures and animals is what turns the animals from destructive to regenerative. ANYONE BLAMING THE ANIMALS INSTEAD OF THE MANAGEMENT OF SAID ANIMALS is an idiot.

  • @nicolasmaciaswoitrin3377
    @nicolasmaciaswoitrin3377 2 місяці тому

    It is important to understand that what Allan is saying is that beef production is NOT necessarily related to grazing! large areas of the world have evolved to support tens of millions of grazing mammals and is them that keep the ecosystem going! Think of the American bison, the wildebeest, the zebras, the buffalo, the auroc, the European bison! The point is to farm grazing animals in those places where they NATURALLY belong and do it in a way they will boost ecological processes. Yes, you can ranch cattle in some parts of north America with ecological benefits. Yes, you can graze cattle in Europe in wood pastures and shrub as it always was (the European mega forest is a myth). Yes, graze sheep and goats in middle east regions and Central Europe's mountains where they are actually from. But how do you erase 500 years of colonial efforts that took graziers all over the world.

  • @aussiegamer1883
    @aussiegamer1883 2 місяці тому

    Wrong Its not extinct

    • @Cons408
      @Cons408 23 дні тому

      Bluds a little kid💀

    • @aussiegamer1883
      @aussiegamer1883 23 дні тому

      @@Cons408 nah mate I'm 18 and I've seen one out hunting with mates and family but aye if anyone's a child it's you 🤣🤣🤣🤣

    • @Cons408
      @Cons408 23 дні тому

      @@aussiegamer1883 they're extinct little Timmy

    • @Cons408
      @Cons408 20 днів тому

      @@aussiegamer1883 plus they're gone

    • @aussiegamer1883
      @aussiegamer1883 20 днів тому

      Yeah no but aye, feel free to keep your own opinion to yourself, they're are alot and I mean alot of people out there that have seen them

  • @rebeccalyon3847
    @rebeccalyon3847 2 місяці тому

    Thylacine is not extinxt people think it is

  • @umayoubm3866
    @umayoubm3866 2 місяці тому

    George seems lost in fake or 'controlled ' science. Allan has history evidence that carbon is NOT the cause or cure to the proplem of desertification. North Africa used to be grasslands untill roman empire killed off the wild animals who were feeding the land is a balanced cycle

  • @galenhaugh3158
    @galenhaugh3158 2 місяці тому

    Evolutionary?????... this wasn't evolutionary!

    • @AMC2283
      @AMC2283 2 місяці тому

      by all means, what was it?

  • @mikecahill3989
    @mikecahill3989 2 місяці тому

    Allan Savory is a True ecologist and a Great Man who has cared about the planet long before Monibot jumped on the bandwagon and skewed the science

    • @prettynoose888
      @prettynoose888 25 днів тому

      He killed 40 000 elephants and you think he’s a great man…WOW!!!

  • @bigyin2586
    @bigyin2586 2 місяці тому

    Is the professor concerned about global boiling?

  • @mayapapaya89
    @mayapapaya89 3 місяці тому

    Fantastic to hear George speak on this subject. The amount of fake news in livestock sector is out of control!

  • @GavinHardy-kh6lr
    @GavinHardy-kh6lr 3 місяці тому

    George appeared arrogant and angry and was attacking his opponent. It's not Allan's fault that his method has not been peer reviewed. In any case, Allan is just getting on with it and showing that carefully planned restocking that mimics wild animal grazing in the dry temperate to arid zones restores landscape biodiversity and reverses desertification. And carbon is also stored in the grasses, not just the soil.

  • @warrenpaine
    @warrenpaine 3 місяці тому

    The 3 largest ethnic groups in the US are Americans of English, German and Irish ancestry.

  • @gaiarhodes9171
    @gaiarhodes9171 3 місяці тому

    Could use this for a pepper's ghost illusion

  • @user-iksd0713
    @user-iksd0713 3 місяці тому

    성게 포유류등의 알은 등황란으로 난황의 양이 적어서 알 전체에서 난활이 일어나는 전활을 하며 동시에 난황이 전체에 균등하게 분포 되어 있어서 난활에 의해 생긴 활구의 크기가 같은 등활을 한다 이 등황란은 식물극과 동물극에서 항문이 먼저 생기는 후구동물 이다 등황란 뿐만아니라 중황란 단황란에서도 식물극과 동물극의 활구가 다 다르다 이것이 진핵생물이 동물의 난활의 방식으로 진화를 해온 유전자의 진홰를 보여준다 등황란은 모아동물에서 극피동물로 극피에서 원색 동물로 진화를 하였으며 등황란의 시작은 어떻게 되었는 가는 밝힐수 없다 이 등황란의 시작이 난의 시작이다 중황란은 난황이 비교적 많고 알의 중앙부에 모여 있으며 세포질은 그 바깥쪽을 에워싸듯이 존재하고 있다 이 난은 곤충 갑각류에 많다 말미잘의 강장동물에서 볼수있다 난활을 할때 알 중앙의 난황은 분열하지 않고 알 표면의 세포질 부분만이 분열하는 표활을 한다 즉 먼저 난황속에 존재하는 핵이 분열하여 증가하고 그들 핵은 알 둘레에 있는 세포질 속으로 이동하며 얼마후에는 핵과 핵사이에 격벽이 생겨 개개의 세포인 활구가 독립된다 말미잘인 강장동물에서 갑각류 곤충으로 진화를 한 것이다 단황란은 달걀과 같이 알의 한쪽에 다량의 난황이 치우쳐 있는 알을 단황란이라 한다 연체동물의 두족류및 연골어류 경골어류 파충류 조류 등에서 단황란을 볼수 있으며 난황이 식물극 쪽에 치우쳐 있으므로 난활은 세포질이 많이 포함된 동물극에서만 일어나고 따라서 배는 접시모양의 배반이 된다 어류 파충류 조류 등의 단황란은 난활면이 알 전체를 통과하지 않고 동물극의 일부에서 만 난활이 일어나므로 반활이라고 한다 개구리 도룡농 등의 양서류 알도 단황란인데 난황의 양이 비교적 적은 동물극 쪽에서 난활이 빨리 일어나므로 동물극 쪽의 활구가 식물극 쪽보다 작은 부등활을 하며 알 전체에서 난활이 일어나므로 부등활인 전할의 전활을 한다 연체 동물인 두족류에서 연골 어류에서 경골 어류로 양서류 파충류로 조류로 진화를 하였으며 파충류 조류의 반활과 양서류의 전활로 나누어 진것은 양서류 6:40 는 습지 생활을 하면서 유전자가 진화를 한 것이다 동물의 진화는 계통도가 아닌 난활만으로 알수있다 난활이 진화의 지문이며 유전자의 지문이다