Wednesday, 5 March 2014

Musings from York


Should we be so precious about only growing native plants?

I frequently read about how dreadful it is to move plants around the world and to introduce alien species into our gardens. A bigger crime is to introduce them into the countryside and we certainly should not plant them into the wild.
A contrary view comes from ecologist Chris Thomas at the University of York. He is the man who predicted ten years ago that a global temperature rise of two degrees centigrade would perhaps over the next thousand years create species-loss of millions. This is on the scale of previous mass extinctions.
In a recent article in the New Scientist, Chris, who has not changed this view, argues that such extinctions have always created the conditions for massive bursts of new evolution. He argues that there is abundant evidence that this process has already started. 
He says that contrary to popular opinion, when foreign invaders are introduced hybridisation will lead to valuable new species. Where Darwin made the analogy of evolutionary steps as new twigs on a tree, modern genetics sees rather speedier jumps in diversity when closely related species hybridise. Genes are more mobile than previously thought.


This is not to say we should not be concerned  about the numerous documented cases where new introductions have invaded new habitats to the detriment of native ecology. More overlooked is where closely related species have given rise to plants and animals with beneficial selective advantages. This might not be obviously apparent where European rhododendrons have combined forces with native American species to create R. x super-ponticum. Nature does not pander to man’s ideas of how it should be. In evolutionary terms this rhododendron is a superior plant!

Ten years ago we stayed on the Bahemian island of Andros. The casuarina trees, known as Australian pine were taking over the island and grew twice as large as in Australia. They were introduced by man for coastal erosion control. This one planted in a hotel garden in Costa Rica is arguably no threat to the local ecology.

One problem with introduced species is that natural predators are often left at home. Japanese knotweed is no problem in Japan! Eventually new predators will arise or be imported by man. A new predator of invasive honeysuckle in North America has arisen by the natural hybridisation of two fruit flies. Actually, even Japanese knotweed is no threat to the wider British countryside. This has not stopped legislation that makes planting Fallopia sinense illegal in the wild. The not inconsiderable threat of knotweed, readily talked up by the extermination industry, seems to be restricted to man made environments such as old industrial sites, general wasteland and old cemeteries. 
Japanese knotweed does hybridise with the thuggish climber called Russian Vine. Not the monster you might imagine. It’s not a good match, a woody climber mated with a herbaceous plant. No hybrid vigour here, more that of a wimp!


Chris Thomas regards the whole world as a gene pool that potentially has the capacity to counter mankind’s destruction. Rather than prevent transportation of animals and plants he argues for open corridors of movement. His university department have moved some of our own native butterflies further North than their previous distribution with very good effect.

I have no idea of the name of this insect, nor whether it is uniquely endemic to Costa Rica or widely distributed, nor whether it would be desirable introduced to foreign climes. What is almost certain is that it’s chances of survival would be enhanced by transportation. But to the detriment of what?


There is an irony that border controls whilst permitting a (restricted) movement of plants have not also permitted their pests! There is a further irony that the worst cases of introduced plants causing havoc are where they have been deliberately introduced by governments for agriculture or control of erosion. Many occasions of unwanted plants having serious detrimental effect have been created by war.

I do not know whether this strangling Costa Rican climber is native or not
Richard Mabey
I have been reading an excellent book about weeds by ecologist Richard Mabey. In it he describes examples of harm caused by introduced plants. He never-the-less takes a benign view to growing and introducing none native plants. I have leaned heavily on his superb book in what follows.

Are there such things as native plants and natural native communities?
After each Ice Age, plants retreated back in different combinations. Ever since early man started to travel, plants and animals have moved and created new stable ecologies. New islands have arisen from the sea and have been randomly colonised with plants and animals of extremely diverse genetic origin. Such islands are evolutionary hotspots and their dynamic ecologies function extraordinarily well.

Walking the beech in Costa Rica I imagined these ocean carried coconuts were colonising a new island. The lower one had success.

Who are we to say what is native? Long before the Romans came to the UK  bringing hundreds of plants now thought of as our own, new plants and animals were arriving. Early human activities, not least hunting, forest clearance and farming led to new landscapes. Over the past two thousand years new plants and animals have been brought to our  shores. Nothing is  completely stable. No environment is untouched by man.

What could be more evocative of England than playing conkers on the village green? The horse chestnut was introduced from the Balkans 400 years ago.
Even some of the as yet unspoiled parts of the Amazon jungle which we regard as pristine, grows on land cultivated by early indigenous communities. The Amazonian black earths, the man made terra preta soils, remain as evidence of land management more than a thousand years ago over South American regions that together total the area of France!

The movement of weeds.
Ever since man started to cultivate the ground, unwanted plants have muscled in and natural selection over thousands of years has led to their superbly efficient strategies of survival in the garden and farm. Everywhere that man has gone he has been accompanied by weeds. Their well honed survival techniques have enabled many to outcompete native vegetation. 50% of New World weeds were brought over inadvertently by the settlers. Having survived many hundreds years of European farmers’ attempts at control, introduced weeds - or should I say wild flowers - easily outcompete native flora.

Despite their success, introduced plants have not lead directly to the actual extinction of native plants. It would be difficult to specify a plant lost to the UK  because of introductions over the last 2000 years. That is not to say that plants have not been lost to man’s activities and changes in climate.
I liked Richard Mabey’s story of Kentucky Bluegrass.The grass has an image to us here in the UK as being American as American pie. Smooth stalked meadow grass was brought over from England! 
Nettles, groundsel, sowthistle, knotweed, dandelion, chickweed, shepherd’s purse, mayweed and couch are just a few of Britain’s gifts to the world.

Planned distribution
My friend Harry Kennedy was a merchant seaman in his youth and travelled the world. He tells me that what most impressed him was not the differences, but the similarities between plants from country to country. Our Victorian ancestors regarded it as their God-given duty to explore  and redistribute plants. Kew gardens was a broker of plants that served the Empire. The world’s plants and social systems were changed with the transfer of rubber, sugar cane, tea, coffee and bananas. Plant explorer-collectors have imported plants for hundreds of years. World agriculture shares numerous crops. Many plants and animals deprived of their natural habitats by human activity have been conserved by their redistribution. The world is a better place for the sharing of plants.

William Robinson.
His book ‘The Wild Garden’ published in 1873 created a sensation in Victorian times. He advocated using the wild flowers and weeds of the world to be planted naturalistically on the boundaries of  country estates. He introduced  from America, solidago and wild michaelmas daisies. He promoted wonderful Japanese knotweed and lovely yellow goat’s rue. Inevitably his plants escaped to the wild. Was William Robinson a visionary or a vandal?

So where do my musings take me?

Perhaps to reinforce prejudices! Here are some of them.

I will continue to fill my cemetery gardens and village plot with self seeding plants of the world.

I do not support the idea that when trees are planted in public places that they need to be native.

My prejudice against that vigorous intergeneric hybrid, the Leyland cypress remains.

I will continue to plant variegated plants and dahlias in my garden.

I will promote the use of insect and bee friendly plants on farmland whether they be ‘native’ or not.

I support efforts to maintain special landscapes whether they are deemed ‘natural’ or are relics of our forbears.

I am cynical about ‘offset arrangements’ when developers wish to develop ‘pristine sites’.

I will continue to point out that there are many instances of habitats for rare plants such as orchids on industrial wasteland that are bi-products of herbicide use. Clear examples of plants’ accommodation to man. Further, that enlightened use of herbicides has a place in land management.

I will continue to admire the fashionable colourful labour-intensive blobs on urban landscapes created as meadows with gaudy agricultural weeds. But they are too hard work for me.

I will also continue to look at the work of Piet Oudolf with a mixture of jealousy, envy and admiration. His methods are too expensive for me. I wonder how his landscapes will mature and how history will regard his skills.

Although it might be desirable to move  animals and plants around the world there is still a place for governmental restriction and prescription.The only present permit from The European Commission for the import of a plant parasite is a psilid fly specific to Japanese Knotweed. Completely free transport would encourage the crooks who despoil natural habitats. Look what is happening to elephants now that the United Nations has allowed the worldwide sale of historic stored ivory. It has provided cover for their slaughter.

I am emboldened to argue against fashionable politically-correct notions of plants we must avoid. I think Himalayan balsam is a wonderful plant. An old rural name is the ‘bee-bum plant’ which is indicative of busy bumblebees deep in the flowers. It is a very pretty nuisance on wet sites already spoiled by man but in my view is no threat to nature.




What hat are you wearing today? Is it the one that maintains only ‘native’ flowers or the one that preserves insects and bees?

31 comments:

  1. Our flora would be very limited if non native plants had never been collected. We would also have a very limited range of food crops if we stuck to that which grows naturally in this country. One plant I do find a nuisance is oil seed rape which seems to leak out from fields into the countryside.

    By the way the bug is a flag footed bug.

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    1. Thanks for the information Sue. With your lead I have now checked the bug out and it seems to be one of the leaf footed bugs. it can be an agricultural pest. Thats the thing with these things, one person's pretty insect is someone else's pest.
      It to me looks like a true bug - as I realise you will know. Sometimes we in common language call all insects bugs. Technically this is wrong and UK examples of the group include the shield bug and (I think) the frog hopper

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    3. I thought I'd replied to this. I think some call them leaf footed and others flag footed, Roger, The head definitely looks like a true bug. Yes a frog hopper is a bug and I never realised that there are actually several species of frog hopper!

      I suppose it's like the lily beetle which is also quite pretty but not welcome when it is in your garden chomping lilies!

      I deleted the last reply before you made fun of my typo.

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    4. Would I make fun of you Sue?!

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  2. You have given the subject a lot of thought Roger. I do not think we should limit ourselves to native plants but we must be careful not to encourage invasive plants. As Sue hinted, as far as food crops are concerned, the majority are not native. Beside, what is native is not an easy question to answer. Because I live in North America, should I consider beans and maize native? They never grew here on their own.

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    1. You are right Alain, not many vegetables are native or in some cases have little similarity to their ancestors where-ever they came from e.g. Brussel sprouts which are quite different from their brassica parents before selection and breeding.
      When you look at vegetables grown in the UK say 1000 years ago the list of vegetables would be limited and contain hardly any we eat now. In fact in my last post I wrote about peppers which have only become popular in the last thirty years.

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  3. This is something I've been trying to learn about for the last couple of years, as my garden is adjacent to woods and meadows that support a lot of wildlife. Over that time I have changed my outlook on things. Although I don't for one minute think garden plants should be restricted to native species, there is one point that is often over-looked, which is that providing pollen and nectar alone is not enough. Take for example moths and butterflies. Both need food for caterpillars. A large number of species are extremely fussy about their foodplant, so a lack of a native species foodplant will have a big impact. But one native species tree can support quite a number of moth species. Which in turn provide the essential food for breeding birds to feed to their young. So I'd agree with putting them in parks!

    Sometimes a species might not be overly fussy...some moths have a taste for salix, and any salix might do. But take for example the Purple Emperor butterfly. It's a big beastie, and it's caterpillar are big too, and they want to hide under a big leaf. So it's fussy, and will only lay it's eggs on a good broad leaved salix. But unfortunately all our garden narrow leaved salix have hybridised with the native broad leaved, so that makes it harder for the butterfly to find suitable plants for it's eggs.

    Up to a point evolution will deal with this, but it's a slow process. The Purple Emperor can't evolve into a smaller butterfly fast enough, so it's survival depends on it's food plant remaining available.
    I do agree evolution will deal with it, eventually. In a million years time, things will be different. But in our lifetime it will be the losses that we see, the phase during which new species evolve will take much longer. I take your point that other insect species could be introduced to correspond with the food supply, but I suspect it's quite complicated too. So my current outlook is to try to be aware that every plant in the wild should be edible for a native or established species, and if it's not, make sure it can't escape from the garden and displace the native plants.

    However there is still much I need to learn, so I could be wrong :-)

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    1. As usual a thoughtful response, Sarah. Quite a muse yourself!
      You have picked up as others have, that there are not many people around who are not happy to use plants of the world in their own garden and it is those who do not like none native plants in the wild that my musings are more relevant.

      I think that none native trees for example, planted in open fields are not detrimental to habitat for native wildlife as you suggest and I would argue that they supplement habitat and diversity.

      And of course as you point out evolution is very slow and Chris Thomas was looking at consequences over a thousand years. Consequences of introductions good or bad are much more rapid than that especially where hybridisation takes a hand. Natural selection of existing diversity in a species can bring changes in a few decades e.g. in changes of colour of butterfly wings, before, during and after past industrial pollution of soot.

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  4. Roger, I know you don’t mind an argument, so here goes:

    Imagine you and I have a field, and we have only space for one tree, some shade for the animals perhaps. We’ve got three trees in mind: a native tree, a Holm oak and a Monkey Puzzle tree.

    The Monkey Puzzle would be fun, and look great from our house nearby. It’s not invasive, so it won’t do any harm. Unfortunately not many species are likely to be able to use it as a food plant, but spiders might find it useful for webs, and a few other species might find it useful habitat. So maybe it will provide foraging for a few blue tits to supplement their diet, but no caterpillars for them to raise young.

    The Holm Oak will provide more food. Acorns, and some insect species that aren’t fussy about which Quercus they eat. So perhaps it will feed a few broods of blue tits, and supplement their winter diet too. Also it’s good shelter in the winter...so it’s definitely providing lots of positive things (I’ll ignore the argument that it is slightly invasive, or we’ll go round in circles!)

    The native tree has a hundreds of species of insects using it as foodplant, and more than the Holm Oak (I don’t know if this is true for a Holm Oak, I’m just guessing, but it will be true for some introduced species). Of the three options, it’s likely to provide the most food across all the seasons for our blue tit army.

    None of our trees are detrimental, so which shall we plant in our field? We only have space for one.

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    1. Can I just elbow in and say I'd choose a self fertile fruit tree which probably wouldn't be a native variety as it will have been bred for it's fruiting quality.

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  5. p.s. can I just change that so the whole blog tribe live at the house? I just noticed that what I wrote looks a bit weird. Bunny boiler weird :-D

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    1. I think it will depend on which hat I am wearing and where I actually have my field. i think it will my 'design cap' and will be looking for gardening interest and fruit and flowers and something that looks natural for the site. It is unlikely to be a conifer and certainly not monkey puzzle It will probably be deciduous. i have planted fifty trees on my acre plot and they are all native to somewhere! I would argue they support a very rich ecology
      When I look out to surrounding countryside there are lots of native willows, some large and very fine trees. I think it is wonderful that the woods harbour nettles on their margins which are hosts to many insects, some fairly specific. I see no danger whatsoever of this plant ever being threatened and do not agree they should have a place in my garden. I do have specific plants in my garden planted to encourage specific insects- I have forgot its name but one composite flower harbours a rare and pretty beetle. It's all about hats!

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  6. Adjoining our garden used to be a 6 acre field of wheat. 9 years ago cultivation ceased and nature took over. The transformation of this area which has been left totally uncultivated and invaded by wild species is quite remarkable. Initially groundsel (aka ground steal) and ragwort, knotweed (not Japanese) and dandelion dominated and now willow woodland and rosebay willow herb prevail. Every year we have a changing set of weed seedlings blowing over. Given the number of kestrels and buzzards we see there must be some animal wild life too. We have interfered slightly ourselves with additions of a few outgrown or under performing trees and shrubs, mainly native or near native. We tend to think of the countryside as a fairly static environment but it is far from it – who knows what the next few years will bring? Unfortunately many of our cultivated neighbours think this bit of “countryside” is a disgrace and “something” should be done. For ourselves we are fascinated watching nature do what it does best.

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  7. PS - but our garden is full of colourful, interesting aliens and we wouldn't have it any other way!

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    1. I envy you watching nature at work and thank you for your lovely description of it Pauline. Let us hope it is not sold for development now that common opinion of it is that it is now degraded!
      I don't know if you have read Richard Mabey's lovely book, an absolute classic called 'Weeds.' In it he describes natural successions on 'brownfield sites' and even cities when abandoned by man.

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  8. I may be missing the point here but when I read the title of your thought provoking post Roger, I immediately think of stable doors and galloping horses, admittedly we couldn't have done much about it 2000 years ago, but as the indiscriminate introduction of alien species has been going on for at the very least 500 years it is a bit too late to be choosy. Many species were effectively introduced almost directly into the wild as the great estates were the main beneficiaries and those that wished to spread into the surrounding countryside did so only if it suited them, which can be seen in the extreme case of the super-ponticums or the ditches full of Gunnera in Ireland or even the invasion of Iceland by Lupinus nootkatensis.
    I am not quite sure how this argument has arisen, as you quite rightly say, surely nobody would object to alien species in the garden and in fact would be hard pressed to find any existing ones that weren't and if it is part of some scheme to turn back the clock, to make up for all the damage we have done to the landscape then this is highly commendable but should not be limited to plantings of "native" flora as with the influx of pests and diseases plus the vagaries of the weather surely the best option is plenty of planned biodiversity. Unfortunately we seem to suffer from knee-jerk reactions and trending, a case in point being the response to the great global warming catastrophe when the horticultural media was telling everyone to buy drought resistant plants and many councils opted for plantings along those lines which resulted in virtually everything being wiped out in the most severe winter for several years, now that was a man made alien invasion!
    I would go further than yourself in liking the Himalayan balsam, I am also quite partial to rosebay willowherb, which along with buddleias do a great deal to brighten up some of our less appealing industrial landscapes.
    One can't totally deny the possibility of some damaging genetic incident lurking round the corner but after all these years I would think that the odds are firmly against it.

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    1. Much interesting stuff as usual Rick. I don't know if you have read Richard Mabey's fine book "Weeds" but the subtitle "How Vagabond Plants Gatecrashed Civilisations and Changed the Way We Think About Nature" tells the story of how a delicate woodland plant was transformed by war into the invasive but rather lovely bomb site lily - the rosebay willow herb you admire.

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    2. I have just ordered "Weeds" and I am looking forward to reading it. The genus Epilobium contains quite a few alpine species of which I grew one several years ago but for the life of me I can't remember the name. One of the most notable species is Epilobium fleischeri, it is actually a moraine plant surviving in some of the most challenging conditions possible. Rosebay willowherb has now been moved to the genus Chamerion, I just can't keep up with the botanists!

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    3. I hope you enjoy the book. Cathi bought it me as a Christmas present. As a publisher she has a 'nose' for books I will like. I found the first chapters terrific, I then stalled a little with herbal history, fascinating as these early medical matters were. For me after these chapters the book came alight again. I will not say I could not put it down because when I have something good I like to savour a chapter at a time

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  9. The fossil record keeps on proving Darwin wrong, and to make matters worse, the genetic fossil of DNA is now proving his theory wrong as well. Fossils show that new species come into existence in a geological 'blink of an eye', then they remain essentially stable until eventually they become extinct.

    Darwin voiced his hopes that fossil hunters would eventually unearth proof that supported his theory of gradual evolution. They have not done so.

    Now geneticist Eugene McCarthy has discovered why there are no missing links, and just how badly Darwin was WRONG.

    McCarthy is claiming that rather than compounded micro mutations, it is the genetic turmoil of hybridisation that creates all the diversity that feeds natural selection. Hybridisation creates new forms of life in just a few generations, and once stabilised, they remain constant until they are in turn ousted by some new more able hybrid.

    So the evolutionary tree, should not be showing one parent, but two.

    Read his theory http://www.macroevolution.net/e-book-readers.html

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  10. Thank you for this fool on the hill! To a fool in the flat vale of York Eugene McCarthy’s book looks very interesting. I propose to read the book carefully before responding to you. I will not check out ‘conventional’ opinion’s analysis of it until I have read it all which will take me a few days.
    It seems to me that Darwin was wonderfully right in his central thesis that a process of evolution occurred and the insights he displays are amazing. Considering even Mendel’s discoveries were not even available and of course modern genetic understanding more than 100 years in the future and epigenics even further away I believe he and Wallace deserve their place in history - it ought to be greater for Wallace than it is.
    My main reservation in saying ‘Darwin was wrong’ is that such statements are grist to the mill of those who deny that animals and plants have evolved at all. I find it ironic that when ‘gaps in the fossil record’ are filled by some further discovery that the two smaller gaps created are offered as evidence of inadequacy! That is not to deny the apparent punctuated advances in the fossil record.
    I will add further comments in a few day’s time

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  11. I take you point about making the seemingly outrageous statement, and indeed I find it necessary to be very selective in choosing to whom I say such a thing in order not to incite a shower of creationism.

    I agree totally that both Wallace and Darwin were giants, and indeed, I wonder if Darwin was all that wrong, or if it is modern science that has 'put words into his mouth'. He observed the rapid progress of natural selection working on the huge genetic diversity created within a genome by some process. I often wonder just how close Darwin was to realising that hybridisation was the source of that natural variation. Had it not been for the observation that hybrids had very low fertility and were often the source of monstrosities, coupled by a religious dogma that any form of breeding across 'types' was a sin, I fondly imagine that he would have twigged this final and absolutely key source of variation. Of course, it was hard enough to gain acceptance that man was a descendant of the apes, I think his book would have been utterly rejected had he suggested that man was the monstrous offspring of an ape with some other animal (ever considered how much like a pig humans are, and that the similarities we share with a pig, are not present in the ape...).

    It has come as a shock to me that, not only did religious dogma round on Darwin's theory, but today, scientific dogma is doing exactly the same to McCarthy's theory. Darwin did so much work hybridising his pigeons, it is a surprise he didn't understand this one missing crucial piece of the jigsaw - or did he? His intellect and perception was probably sufficient for him to realise that this would be a step too far for his society to accept, so perhaps he elected to leave it for someone to realise when the time was right - I like to think this might have been the case.

    The role of hybridisation in evolution is critical and it explains so much. For example, extinction is a logical prediction that stems from McCarthy theory. Hybridisation between two differing genomes, creates a massive storm of genetic variation, most of these are non viable (hence the observed low fertility and formation of monstrosities), but natural selection not only culls the non viable out of this diversity, it also selects for survivability and fertility. Once a 'type' has established itself, natural selection continues to select for fertility and constantly whittles away at genetic variability. Eventually, a 'species' is formed with little or no genetic variation remaining. This genetic purity, leaves the species in a genetically sterile 'dead end' with no ability to adapt to changing environmental needs. The moment a new hybrid is formed with sufficient diversity to adapt to new circumstances, the old 'species' is driven into extinction.

    Another important aspect of viewing evolution from a hybridisation perspective, is that it deals a death blow to the idiocy that seems to be infecting conservation organisations, of destroying prolific hybrids. They are standing in the way of evolution and potentially destroying the diversity that is needed to cope with our rapidly changing world.

    I look forward to hearing your thoughts when you have read the substantial McCarthy papers.

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    1. I was already starting to think before receiving your second epistle that Darwin who was so reticent about publishing his theory into Victorian society took a political decision not to attempt to discuss something as radical as hybridisation. It would never have been published. As a child I was aware about hybridisation from gardening but when I speculated about it in a school essay on evolution got fairly short shrift from my teacher
      Chapter 3 today!

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  12. Wow, how ironic.

    Is your teacher still alive today? If so, send them a link to McCarthy's site on Macroevolution...

    Have you reached the part of human differences from apes and the missing daddy of homo sapiens?

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    1. He would be over 90 now!- no not the missing daddy - He was actually great teacher at night school. I had to go there because my NE school in Hartlepool did not teach biology - it was a girls subject but I needed it for horticultural college.
      I am devouring Eugene MacCarthys book and will be reporting back soon!

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    2. What an amazing book and what a radical new look at the processes that make up evolution. The concept of hybridity has been there at the edges of evolutionary theory for a very long time but MaCarthy’s brilliant insights promote it to that of the driver of life’s evolutionary advance.
      We have in recent years become accustomed to the malleability, plasticity and mobility of DNA by both natural and artificial means and have come to understand the transfer of genes by such mechanisms as the following examples;
      horizontal gene transfer in microbes and transfer of resistance to antibiotics from one bacteria to another,
      mitochondria and chloroplasts having being originally subsumed by one organism of another,
      virus and bacteriophages having inserted new genetic material into genomes over evolutionary time.
      We already are comfortable with hybridisation to produce new plants and accept that most agricultural crops arose as hybrids as did some farm animals.

      It is not difficult to accept that when it is explained that hybrids do stabilise and that crosses can be viable between quite distant plants and animals, that hybridity assumes a much greater significance as the engine of evolutionary process. Far greater than Darwin was prepared to recognise.

      I have been recently reading the book series ‘Earth’s Children’, Jean Auel’s lovely novels where she imagines that there were rare occasions Neanderthals hybridised with Homo sapiens and where she so beautifully handles the social issues that must have arisen and how the unfortunate hybrids grew up to mate with their host clan. Since then, analysis of our own genome does show genes from both neanderthal and denisovan origin.

      I have previously taken the view that gaps in the fossil record were gradually being filled. It does seem that both ancient and some modern palaeontologists are adamant that new animals and plants do suddenly appear in the fossil record and then remain stable with very little change, even in some cases e.g. Metasequoia glyptostroboides over millions of years to survive to the present day. Hybridisation elegantly explains how such discontinuities in the record occur and that a line remains relatively unchanged until extinction.

      it is ironic that my post that partly concerned maintaining existing ‘native’ species despite ‘foreign’ introductions that hypothetically may threaten them or even hybridise with them should lead to you, Mr Hill-Fool, make me recalibrate my thinking about evolution.

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  13. Welcome on board Roger, the world really does become a different place when you see it from the perspective that we are all happen stance lucky hybrid 'monstrosities'. It explains why 'Natural Selection' has failed to eliminate some absolutely stupid errors - because we are monstrosities, full of stupid errors, but good enough to get by and make a place for ourselves in the world.

    I wonder what Jean Auel would make of McCarthy Theory?

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    1. Hello again Mr Beatleman
      I am making this comment in case you get an alert e mail of my reply to your last comment!
      I have dedicated my latest post about hybridity to you. If it does not go well I will blame you instead!

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