Cafe Scientific, Southampton, UK, past talks , 2010

Some details on recent SWA science cafe talks
Some details on SWA science cafe talks of early 2011
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Latest update of this file 25 Sep , 2011
Some summaries etc of past talks held at the venue, The Southwestern Arms (upstairs room) , 36 Adelaide Rd, St Denys, SO17 2HW
Some hosts are not alowing remote linking now , so to view a "forbidden" picture you have to right click on the mouse and select "view". Not verbatim, and there will be homonyms, transcription, transliteration, typing and spelling errors in the following write-ups. Q&A , grouped under one "Q" tend to be dialogue with / multiple questions from one enquirer. ? for unheard / masked words , ??? for phrases.

12 July 2010
Title: A 21st century plague - some reasons for failures/problems in electronic equipment.
Why do the medical /aerospace/ nuclear and defense electronics manufacturers have an exemption to allow continued use of traditional leaded solder ?. Basically , planes falling out of the sky or nuclear reactors going critical is perhaps a bad thing. Issues surrounding the use of lead-free solder in electronics products sold in Europe since 2006, tin-pest , tin whiskers, poor solder joints and related matters.
Speaker: Nigel Cook Powerpoint text and a couple of the speaker's pics s/ A 21st century plague Issues surrounding the use of lead-free solder in electronics products sold in Europe since 2006, tin-pest, tin whiskers, poor solder joints and related matters. Why do the medical /aerospace/ nuclear and defense electronics manufacturers have an exemption to allow continued use of traditional leaded solder ?. Basically , planes falling out of the sky or nuclear reactors going critical is perhaps a bad thing. s/ Straw Polls 1/ Is electronic equipment more or less reliable in the last decade compared to the 1990s ? 2/ How many people here tonight have had problems with electronic equipment in the first few years after purchase? s/ History Late mediaeval organ builders Tin-mercury mirrors s/ Mirror silvering damage s/ Recent History Japan passed the Electric Appliance Recycling Law, April 2001 "The soldering on every aspect of Sony's DCR-TRV 30 digital camcorder, released in March 2001, is 99.7% lead-free, including all supplied accessories. s/ RoHS & Weee, 2006 s/ Elemental v. Salts of lead Water pipes since the Romans Tetra ethyl lead Leaded paints s/ Try the forgiveness test on samples A,B& C One leaded, the other two are lead-free One is Lead + Tin SnPb, one is Tin+ Silver +Copper, one is Tin + Copper s/ What is a printed circuit board? Through board Plated through Surface Mount Copper Trace Solder joints Ceramic & metal components s/ Lead-free signage s/ Tin whiskers s/ Tin Pest / Tin Disease Tin pest starts at 13 degree C, not minus 13 degrees Eg, air freight from the orient 17% increase in volume to grey tin and a semiconductor s/ Tin pest on one pin only Top one still mainly silver-colour but lower one, the PbF tinning is converted to an insulating grey tin surface, in this pic. That pin had no mechanical and so no electrical connection with the circuit.
tin pest
s/ Common failure points
"kettle lead" IEC connectors
1/4 inch jack sockets
components like volume controls routinely touched by hands 
A crack developing in a solder joint around a pin, 1mm radius to the pin centre at X , viewed at a
a slant angle, note the striations on the surface , often seen in PbF
 cracked , failing PbF joint
s/ Tin pest 
s/ Just plain bad solder joints 
s/ Eutectics the magic of solder
s/ That extra 30 degrees 
s/ Testing for lead / lead-free solder
Appearance volcano or dome
Indentation test
Low temperature soldering iron test
"pencil lead" test
chemistry HCl And KI , orange tin iodide and "gold" lead iodide
s/ What do the military do now most production lines are lead-free
De-balling and re-balling Ball Grid Arrays etc
s/ Like-for-like testing
comparing leaded and unleaded solders on otherwise the same boards 
subjected to HALT accelerated aging by vibration , temperature and humidity cycling.

followed by about 3/4 hour of Q&A

Monday 09 August 2010 Talk, by Chris Jackson, Works chemist with a Hampshire based natural products processing company .
Title: The manufacture of citrus oils and plant oleoresins for the food flavouring industry.
Manipulation of natural fruits , herbs and spices, processes involved and issues surrounding pesticides, plasticizers and packaging. Exploring tinctures, extracts, terpenes, oleoresins, solvents, milling, pelletising, quality control , pesticide analysis and other potential adulteration. A chance to experience some of the exotic concentrated fragrances such as limonene , bergamot oil etc on fragrance smelling sticks.

Background to extraction processes like percolation and batch vacuum distillation , usually 4,000 litres in a batch for a week, at 10 mBar and another more specialised vacuum distillation at 0.05mBar , under vacuum to avoid thermal degrading of flavours. Use of solvents like ethanol . Cirus oils and ethanol have very similar density and by involving water and consequential emulsions it is possible to separate. Then filter processes to clarify the tinctures - origin of alcopops as well as food flavourings. Non alcohol imbibing cultures use propylene glycol instead of ethanol. The USP of the talk was being able to smell some of the concentrated oils such as those of orange, lime, mandarin,tangerine, grapefruit, vanilla, limonene (found in a huge variety of products) . Grapefruit terpene smells clinical or plasticy or paint stripper smell, often used as a de-greaser. Herbs and spice extract resins using acetone or hexane as a solvent. Chance to smell basil , ginger, paprika , spearmint, menthol. Then an incredibly strong and disgusting smell - valerian. From the roots of a plant but requiring sample of the concentrate to be in a screw-cap topped bottle , inside a sealed plastic bag, inside a screwtop jar - triple containment. Time to go outdoors, as just removing from the outer bottle you could smell the dog-faecies type smell a couple of feet away, before opening the bag or the inner container. Standardising - mixing cheap and expensive components. All these processes produce a product that has a much longer shelf life than the original sources and a standardised form for mechanised processes in the food industry. A sesquiterpenal oil that costs 1000 pounds a kilo and other exotic oils massoia (coconut flavour) , cassia oil, coreander oil and another rank smeller from the comfrey plant. Talk and Q&A merged together, total duration about one and threequarter hours ps I met the speaker socially a month later and asked him to verify that he'd been processing fenugreek at work that day. Taken aback, he'd not but a colleague had been . He came into the lab ,housed in a different building, and spoke with Mr Jackson for 10 minutes and left. The smell had lingered on his jumper 10 hours later. Just from that marginal contact - no handshake or papers transferred , just talking.

A presentation by Martin Straw on dowsing on 06 Sept 2010 Topics Proof that flowing water can be detected by wave emissions Calculating the emission frequency Using tangent calculations to identify the depth of a target How quantum entanglement provides a step towards proving esoteric/questionable activities like map dowsing Why Glastonbury Tor has such a reputation for questionable emissions such as ley-lines . In the most part enlarging on the topic of these posts Exploring , via dowsing, the water and geology interaction with black band ironstone and seasonal variation under Jacob's Barrow, on the Wiltshire/Hampshire border

30 Sept 2010 "Robot Companions: Care, Friendship, Sex?" An intro on where the technology is and then some perspectives on the issues. Followed by a discussion on the ethical and societal issues around robotics. Led-off by Vivienne Parry (ex-Tomorrow's World) -technology writer introducing insights by; Dr Alan (Winfield ?) - roboticist developing humanoid robots with HP UWE Bristol, Dr Blay Whitby - technology ethicist , and Joanna Bryson - reader in computer science and artificial intelligence at Bath University. (heard names only, so maybe misspelt) Scicaf held as part of an EPSRC (Engineering and Physical Sciences Research Council)robotics mini-conference/retreat in that week, organiser of the "roadshow" Dr Stephen Kemp EPSRC/robotics. Targeted to the public with any qualms about robotics, to voice their concerns, with responses from people within the robotics community. Two and a half hours of very animated discussion among about 35 people at the meet. About 8 million robots in the world but vast majority are industrial , deliberately keeps away from humans and not in people's homes , let alone in intimate contact . Japan and Korea are leading the introduction of robots in a fome environment. But the biggest problem is safety in this context. Then a concept called "uncanny valley" from the graphical plot of human waryness of robots versus a horizontal axis of their degree of human likeness - a valley shape as most people are very uneasy with the most mechanoid but also the most human-like. Sex and robots . Reference to a book by David Levy "Love and Sex with Robots" . Apparently people are having sex with robots at the moment. Can you love a robot and can it love you back.? Will the concept of love change? Robot pets in care situations . There are the 3 laws of robotics but what ethical constraints are there on the developers of robots? is it ok to beat-up your robot girlfriend? Apparently when cable TV enters an area the amount of sexual assaults goes down- would the same occur with sex robots? A Stepford wife anyone? Is an ethical military robot an oxymoron? Concerning attitudes to animals , do they migrate across to attitudes to robots. Do pet dogs love their owners.? (Some) humans have sex with animals , so what difference moving to robots instead? Willingness of deciept when there is commercial imperative to stop human-human interaction , in favour of human-robot interaction. When will there be a robot defendent in court? in earlier times animals have been tried in courts for murder etc. followup email from the organiser I know what you mean about entrenchedness. I think a number of eyes were opened. Even the main meeting, which was closed and Chatham House-ish, opened eyes simply because it brought together roboticists with humanities people. They've now realised there's so much more to what they're doing (ie so many more voices in the conversation) even before they move out of academic circles! We're now thinking about an interdisciplinary network to bring together many more roboticists with humanities academics as a prelude to more widespread engagement. and some background to the EPSRC retreat

11 October 2010 Paul Cripps, geomatics manager of Wessex Archaeology, Salisbury. Wiltshire Title: "Laser-beams, spacecraft and archaeology; recent approaches to the recording, analysis and interpretation of cultural heritage " and 3D graphics presentation . Synopsis: This talk looks at one aspect of archaeology; archaeological geomatics, that is the use of spatial information within archaeology. It covers some of the latest advances in technology as used within a large archaeological unit for the recording, analysis, interpretation and dissemination of archaeological information. As well as covering the various technologies, there will be case studies to show how these new technologies help archaeologists understand the past and share this understanding. 3 hours of extended talk and demonstrations and Q&A with 1/4 hour break in the middle. Geomatics - GIS geographic information systems, spatial database systems, maps and survey technologies. Archaeology has a long history of using and adapting other disciplines's technologies . He had brought along a number of pieces of the survey kit. Metric survey systems like total station using lasers for angles , direction and distances and positioning via GPS and integrating together. The outlier prism reflector station can be radio linked to the measurement station so one person operation. For building recording use of a larger ruggedised laptop with autoCAD on it , in place of the small built-in screen of the reflector station. Producing a 3D image there and then in the field 13,500 GBP piece of kit. Laser scanner automatically captues tens or hundreds of thousands of data points. Subdivided into time-of-flight scanners EDM fashion, left to its own devices capturing everything in view including disembodied humans, used for big stuff and a resolution of 1mm. Other type is the triangulating laser scanner instead of rotating mirror, the mirror is offset and can capture much higher resolutions of 100 microns but only over a range of a few metres. Used on their Stonehenge stones surveying. Time-of-flight scanner an be mounted airborne as Lidar , along with GPS plus attitude sensors, giving a virtual land surface, over squares of kilometres. Environment agency flood-plain monitoring provide them with a lot of the data,flying high giving 1m resolution and .2m in the z axis. Ireland hillforts using this technique on helicopters , flying low, giving 5cm resolution and 1cm vertically. Forestry Commission work shows the technique can survey the ground through the overburden of trees by statistical manipulation. Survey kit getting smaller all the time. Minolta triangulating scanner used on their survey of Stonehenge. Captures everything in a room except directly under it. Data sets are called point clouds x,y,z plus colour , intensity of returned beam. Capturing tens of gigabytes of data - to run an application off his laptop using such a huge dataset he was using an external hard-drive for the point cloud, not running prepared video . Manipulating them realtime in the lecture. Using multiple scan positions to avoid shadows , then stitched together or registered using spherical mirror balls as references on the original surfaces or recognisable key posistions across datasets. The points need aggregating into surfaces and interpreting which surface is which. One approach is called surfacing, fitting 3D surfaces to the point cloud statistically, placing surfaces, then CAD cleaned up, then adding light and shade. Latest developement also demonstrated later on is ability to work directly on the datacloud without going through this intermediary stage - digital surface model, then lighting effects or geometric analysis of landscapes. 1m resolution dataset of Lidar called up to "fly" around the wider Stonehenge and Amesbury area. Because of low resolution the Stonehenge stones were curiously rendered as pointed structures not the iconic square arches. 40 sq km, 133.5 million measurements to give slope maps, hill shades , aspect maps, contours. The intensity return gives some idea of the material it has bounced off so can give crop marking differentiation of underlying archaeology, but not necessarily any corresponding observable surface features . Reduction process to reduce the dataset to polygons as more manageable. Can stretch a digital representation to enhance height changes. Accessibility shading - like an inked ball rolling over a surface and only painting points of contact. Colouring the dataset. Oblique lighting to simulate very low sun angles, easily done with this processing and "sun" at any azimuth angle. Dynamic lighting brings out details , polynomial texturing via HP,Bristol developing, can be applied to small finds. Composite images together and moving the virtual light around picked up different field systems and different structures appear at different features at different angles. Orthographic images like traditional rectified photography is one output format, metrically accurate pictures. British National Grid and benchmarks tied the survey data in , superceded by GNS/GPS/dGPS. Within 5 minutes his stand alone GPS unit posistions to mm accuracy , can be fixed to the top of the total station giving a one-stop shop. The people digging the site can now survey the site wthout requiring specialists to come in. A pair of small hand units , much more accurate version of car sat-navs, for walkover surveys. Differential GPS, dGPS these days does not require 2 units, master base station and slaves. Can simultaneously use all the satellite systems , USA,Europe and Chinese, resolves any differences within the unit itself. Has a mobile phone built in and keeps in contact with Ordnance Survey Smartnet system of active base stations that have replaced trig points -hence mm accuracy. GIS can go out into the field now with mobile phone apps., Stonehenge Landscape Tour demonstrated Stonehenge laser scanning showing carvings that are otherwise difficult to see - axes, mushrooms, daggers or whatever they are. Previously using "brass -rubbing" and latex covering. Photographic methods had not worked very well. A number of the carvings with the new technique had not been seen before. Castle recording , working on that week , billions of data points, 36 GB of data to mm precision the complete Tamworth Castle. The primary dataset should always be archived, so big that they cannot use optical media , hard drives sent to York Archaeology Data Service via courier. Curating digital data is not that straightforward and are using server-based systems, (eg BBC Domesday Project laser disc now defunct). For resolving any anomaly at the interpretation stage, at the same time as the data cloud is made then colour digital photos are taken also. It is also possible to add a panoramic camera head on the tripod instead of the scanner in the same position, capturing hexagonal images to be stitched in easily. Demonstrating recently scanned Henry V111's Sandsfoot Castle, Weymouth (actually sited inside Portland Harbour breakwater now), off his laptop being able to zoom in for very high resolution and pan around the whole castle. Ongoing work to differentiate rock types eg 5 different types of limestone in a castle could be resolved by the scanning but not yet. Polished marble does not scan well , similarly window glass and damp surfaces, as can mist at 100 -200m range and snow reflects/absorbs/refracts. Scanning at night is perfectly possible. Not always possible for H&S reasons and heritage sites cannot keep the visitors out during the day so people tend to be "captured" in distorted ways especially stationary people , masking off the features behind. 2 days to scan Sandsfoot castle and about 3 weeks in the office to do the processing and fitting together. Then archaeological work on top of that. All the optical instruments have to be regularly calibrated, GPS kit does not. AutoCAD is bad at holding millions of data points so data server systems tend to be used for application use. Only the data relevent to the user's area of interest is served up to be rendered at any particular time. An animation melding together OS map data , airborne Lidar , terrestrial laser scanning data , included a snakey feature , which was not archaeological but a residual atrtefact of the processing. A common problem with scanning and processing. Airborne data does not have any colour data. Another animation of the post-ice age landscape , now flooded by the North Sea between England and mainland Europe. Savernack Forest "stripped off" revealing surface topography . Shifting datums and shifting land surfaces have to be taken into account. Greenwich is still considered zero reference point. Salisbury Plain, Defence Estates, captured and enhanced graffiti on trees made by WW2 American soldiers , using mathematical techniques to "ungrow" the trees to go back to the original carved form. Work in progress between Leica and Wessex Archaeology a technique to digitally remove vegetation, such as grass and shrubs, from scanned images. For tree removal deciduous trees "disappear" easier than pine trees due to foliage density. Heritage 3D unit is confronting the problem of archiving datasets that have almost as many data formats as there are types of scanners.

08 November 2010 A powerpoint presentation by Patrick Gallagher ,consultant cardiovascular pathologist at Southampton General Hospital,, to coincide with National Pathology Week, 1-7 November 2010. A talk about Pathology in general and the work of Pathologists and a focus on Pathology and Heart Disease. Pathologists are many different types of doctors and scientists. Most numerous sub-branch are histo-pathologists , disecting tissue and making precise microscopic diagnoses hopefully. Including molecular processes influencing treatment and prognosis. Only about 10 percent of the time, considering all pathologists, would be doing post mortems. A disadvantage of being a pathologist is you seldom meet any of the patients. If you don't like looking down a microscope then pathology is not for you. Silent Witness has done amazing things for recruitment. The majority of autopsies are done to establish why someone has died suddenly or unexpectedly. Haemotologists can work equally in the lab and the ward. A young leukaemia patient, with stomach tube because of side-effect of the drug regime. Microbiologists plan the treatment of infectious diseases and antibiotics . Major role in countering hospital-acquired infections. Example of puss plated-out amongst various antiboitics in a dish to establish efficacy- a very old technique. Imunologists study how the body reacts to foreign substances, colaborating with haemotologists , microbiologists and oncologists . Focusing on the work of Edward Jenner of smallpox fame. Saulk a vaccine for polio. Institute Pasteur in Paris with a museum devoted to him, not just humans studied for he discovered how to tackle a disease of vineyards. Pathology developed from anatomy - Galen dominated for centuries - disease from "humours". Abithinus of Uzbekistan said that medicine is not a hard and thorny science. Proven by himself enrolling at Bukara medical school at age of 16 and qualified by age 18. Writing text books, studying wounds and healing. His text book published in 1020 still being used in French medical schools in 1650. The anatomy theatre of Padua , steeply tiered galleries with less than a 1 foot of standing space at each level. And a hinged disection table for the occassions when papal authorities raided the theatre and the body could be slid directly into the river below. William Harvey just before 1600 could look at veins and they had valves, an observation vital to his postulation of blood circulation. Also in Padua a founding clinical pathologist wrote a text book of case histories and subsequent PM examinations . Sir William Osler , born Canada, later Oxford teaching medical students with a patient. On average , eveyone has 14 pathology tests done a year. What is health ? what is disease ? what do we know about the causes of disease ? and how is the incidence of disease checked.? Histopathologists try to establish a disease identification from taking together case history, examinations and specialist examination. Walking around supermarkets they take a "perverse" interest in making instant diagnoses of people with various conditions. Pathologists and radiologists have a major role in confirming diagnoses and responses to treatments. Pathologists are notorious for making lists and clasifications. Leading to prognoses. Prevention can also come into considerations. Aetiology and Pathogenesis of breast cancer, rheumaoid arthritis - initiation process still unknown, cause not being known does not negate a successful treatment. Inherited conditions and inherited resistance, or not , across cultures. 2 people with Downs syndrome - one obvious and the other not obvious at all. Tissues at the back of the head at ultra-scan stage maybe enough to initially diagnose Downs. Trauma , degeneration in old age , tumours and psychological elements. Pathogenesis - mechanism of the cause and aetiology the developement, becomes the disease. Fractues - trauma over and above the inherent strength of a bone. Sickle cell disease, gene abnormality for endoding for haemoglobin protein. Single amino acid change is sufficient to form sickle shape leading to sloughing and skin ulcers . Evolution should have eradicated it but the sickle cells are remarkably resistant to the effects of malaria so a paradoxcical trait compounds the matter. TB discovered by Robert Koch in Germany and now IV treatment, John Keats a sufferer. Chest Xray with nebulosity of the inflammatry mass. PM slide of a TB lung and microscopic image of the causitive organism with a thick and waxy coat that prevents it from being destroyed in the atmosphere or the patient. Similar cause to origin of leprosy and micro-organism indistinguishable down a microscope but leads to 2 completely different clinical diseases. Smoking and cancerous lung. Input of epidemiologists. Malignant mesothelioma, asbestosis. Slide of asbestos fibres in a lung . Indirect 2 or 3 cases a year in females locally around Southampton, usually wives of dock workers 200 to 300 cases a year. A woman who worked for 2 years as a secretary in a local shipbuilder's office but the 2 or 3 message passing visits a week through the workshop was enough to give her asbestosis. Study how the incidence of diseases vary , stored in such as cancer registries , patient and type of cancer recorded on a database - no patient approval required. In Holland a bigger and more general equivalent, not just cancer. 3 percent reduction of heart attacks in Holland each year for 20 years from monitoring countrywide treatment outcomes. Low socio-economic status determined as an important factor , known from the 1960s. Under or over fed , then risk chances increases. State of health during pregnancy and racial factors independent of environment. Psychological reactions to disease situation are important . A sample of the Q&A Attitude of pathologists to Gunther von Hagens? . Pathologists have got a bad name in the media from events in Bristol etc , pathologists felt that any publicity is good publicity. He's not convinced personally that he learnt anything in the disecting room . Why is it still difficult to counteract viruses? Drugs against HIV are a worthy exception. Our hospitals are not clean but a sub argument that a bit of dirts can be useful for building imunity. Mud tramped into general corridors and then cross transfered to doctors etc onto wards. Is it just identification from microscopic observation of a biopsy slide? Staining processes give some discrimination and now identification of proteins within the tissue by imunological processes but even then not absolute confirmation. What is average time between arrival of sample and test result ? 2 weeks is national target but for cancer tests it could be overnight from late afternoon to first thing next morning. A lot of careers in pathology are available to scientists as distinct from medical training. Future developements ? A slide would be high resolution scanned , along with clinician report , transmitted off shore and assessed abroad. At treatment planning stage there will be a pathologist who will show the histology, say breast cancer grade 3 and the molecular biologist would show the gene reponsible for normal and abnormal expression by the tumour. A composite view would then direct the treatment plan. For a heart patholgist - the Mediterranean diet pasta , fish , veg, red wine etc seem to be the ideal diet. If you can reduce the amount of fish and chips eaten then all to the good. Environmental chemical effects and testing of chemicals for mutagenesis , irritance etc. Is testing on rats adequate for translation into human biology. Case in point thalidamide showed no problem on rats. 8 hour exposure levels with workers in the chemical industry, what about copier toner in officers. His training professor if told that stomach ulcers were caused by bacteria on the stomach lining he would have declared - go away, an Australian pathologist and his summer medical student demonstrated the organism that was the cause.

13 Dec , 2010 about 28 people , about 2 hours in total Powerpoint and talk by John MacNabb, director of the Centre of Human Origins, Southampton University, involving aspects of human evolution. Genetics, becoming more and more important in exploring the pattern and evolution of our species, beyond the normal evidence of tools, skulls (3 skulls as props) and arachaeology. Work in progress, nothing definitive, nothing finished. Diagram of brain size v. time 3million years ago to 100.000 ya. From primitive austropithicine, through variations to modern. As our brain size gets bigger so does our species change. Change of skull size and shape- Homo-Heidelburgensis 2-300,000 years old to present - morphological and tissue changes of that time. Genetics and DNA coming into play only in last 25 years. DNA does not last that long , Neanderthals (called N here) 40-50,000 ya is about the limit of DNA survival in bones. 4 of the big questions involving genetics Origin of our ourselves origin of Neanderthals, our nearest cousin why they became extinct the dispersal of our own species across Earth. Geneticists track these changes, building up this history over time. Graphic of time v representative simple sample of some genes over that time. Each new generation gets 50 percent from each parent and in that process can create Random Copying Error , a gene will mutate. Happens at a failrly regular rate. Some can mutate on more than one occassion repeatedly. Geneticists use the mutations , after x-thousand years a certain gene will have mutated. A modified mutated gene is called an allele and is the focus of attention. Not really tracking people, tracking lineages of mutations. Like a family tree of mutant genes. Since 1859 has been discussion on how evolution works , is evolution progressive?, what its nature and character might be. Genetics gives a more reliable handle on the ancestry rather than just the previous morphological change interpretation. Evolution is just a change in a gene pool over time and nothing else. (Intrusion by a policeman making a parking /vehicle enquiry with 3 human skulls placed on display on the table in the room). Change of species is another matter. Who are humans, where do we come from and why are we like we are?. The earliest is from Africa and 2 very specific discoveries Omerkibbish (90 - 195,000 ya) and Ethiopa Herta 160,000 ya . Our species is no older than 200,000 years. 2 different types of DNA - nuclear that comes from the nucleus , the 50/50 inherited DNA and mitachondrial DNA the "engine" outside the nucleus , its own DNA , only passed down the female line. Mid 1980s emerged we are all african under the skin. Mitachondrial "Eve" the very first woman , but was not one single woman as a male is also required. Not just one woman and does not mean she was the first modern human , but one of a breeding population , just that her's is the only mitachondrial lineage that survived. She had to have 2 daughters at least, various extinction events, other members of that breeding population passed on their MtDNA but in time all those died out . Hence the out of Africa concept . Then allows tracking the dispersion of these little mutations within MtDNA over time. Eve comes from a lineage called L , L2 or L3 very old which evolved from L in Africa , one important for us was L3 , found all over Africa from N to S. 80-85,000 ya outside of Africa we find L3 in Iraq , Iran, Pakistan , the first movement out of Africa , L3 is still very dominant in modern tribes of those areas. Over time daughter lineages occur , more mutations, one is called M , when sampled to the East they find all modern humans have M and various M descendents but not to the West , other ones there. M moved E about 6-65,000 ya , Australia is occupied in S Aus about 45-46,000 ya , in Indonesia earlier than that , archaelogically dated, M21/M22 in Malay , in the Anderman Islands. M31/M32 slightly more recent arriving about 60,000 ya from the genetics , matching between Archaeology and genetics. Not absolutely precise as anything in archaeology that is precise is usually wrong . As M is getting into Asia 60,000 ya there are daughter lineages of M , called R , centred on Iraq and Iran , 45-55,000 ya , new group going Europewards . Daughter lineages of R will meet the Neanderthals , already in Europe before that time, U5 is this first group of modern humans in Europe. U6 are the Burber people, very insular people. U5 have daughter lineages over 30-10.000 ya , but other populations are constantly moving in . Europe without borders, neolithic period and farming developing, there are still new peoples coming in to Europe - a melange of genetics. Origin of Neanderthals Skull shape is quitte different to a modern , not so high vertically but long front back dimension , flattened top and very big brow ridges , different orbits , brain size the same as ours, often bigger - dumb Neanderthals ? Skeletally Neanderthals are decended from Homo-Hedelburgensis , only European , never found outside of W EurAsia. In the last few weeks a paper has been published led by Endecot a geneticist and paleoanthropologist Prof Chris Stringer ,as genetics allow dating of mutation changes , theoretically they can go back and figure out the time when there was the last common ancestor of modern humans and Neanderthals . Then see what species were around at that time and map the 2 together. 4 possible scenarios/interpretations , how that process worked Data results are for 54 modern humans and recovered 5 sets of data from 5 Neanderthals. The last common ancestor was about 410-440,000 ya . 4 different possible timings . Late model, early model, middle model , early middle model. Neanderthal coming out of 410,000 ya cannot work because its CA is too recent Early model does not work either as you cannot have a CA earlier than when CA emerges Remaining 2 include Heidelburgensis May 2010 , in Science, brought the first entire sequencing of a Neanderthal . Based on 3 bones, of 3 individuals, in a cave in Vindija Croatia. Using nuclear DNA , Neanderthal DNA does not exist in African modern humans, reassuring confirmation from the genetics. In all modern non-African people , there is between 1 and 4 percent of N DNA. Present in all Europeans, Chinese, SE asian of Papua New Guinea. So how were modern humans and N interacting ? If there was N DNA in modern humans , how would you argue it ? Some mating going on ? cannot be the case as N DNA in Chinese & Papua New Guinea. In Africa there is some DNA that is very old indeed only in a small subset region of Africa , from this population modern Humans spread out . Modern humans in Africa without N DNA and modern and N moving out carrying this ancient DNA with them is a possibility. Geneticists prefer this hypothesis - all modern humans coming out of Africa , outide of Europe, meet with N , problematic as all N are just in Europe , not in W Asia etc . But some archaeology suggests about 70-80 kya the first L3 lineage and later daughter movement , similar may have happened earlier. Modern humans moved and then stayed in one place , Israel coast, behind M Carmel, 2 caves of interest Taburn and Skull, N living there and modern humans, the earliest outside of Africa. Timeline N 120 kya, modern humans at Kapse and Skull 100-120 kya and 190 kya then modern humans vanish, N return 40 -60 kya . Scenario 100-120 kya movement of modern humans out of E Africa , moved into Haifa area . A successfull migrant need not be a successful colonist . A modern migrated, integrated with N but that movement did not succeed, dying out . As conditions changed or something , they moved back. Because those that moved back carried a small amount of N DNA with them. So the first movement out of Africa failed perhaps, so only 1 to 4 percent contribution. Further daughter lineages moved to the W and the E, now carrying some N NDA. The only explanation so far for such a small amount of N DNA into modern humans. Later interaction would have meant a lot more N DNA . Explanation of early date and very small amount. One theory that is very popular but may noit be the truth . What does this N DNA tell us about the N themselves ? Of 3 million base pairs in the N genome only 78 alleles are different , that 1 to 4 percent difference. The difference between you and this N skull is 78 small mutations, producing a very distinct difference in the skulls. Why such a difference with so small a number - one way is these genes control the developement of bone. Certain bones relate to where these alleles are on chromosomes. One of those positions is to do with the clavicle and anatomicaly could not raise their arms up and so not throw spears. They may have been using thrusting spears. Differences in cognitive developement , many genes associated with conditions such as autism , Down's syndrome, schizophrenia etc are not present in N DNA. The alleles relate to amino acids that switch on and off affecting the developement of these conditions rather than being directly causitive. Skin and pigmentation alleles , even how sperm swim . Maybe N reproduction was slower. The "ginger" gene , all N were ginger so they died out was a press favourite. Allele that controls skin colour is MC1R , darker pigmentation to protect against sun UV in Africa. The amount of sunlight we are exposed to in Europe is less and we lost it. Taking away of selective pressure rather than Darwinian force for change and these alleles left in limbo and drifted into alleles for pale skin and ginger hair and other pigmentation variations as well . Some proportion of N would have had fair skin and red or ginger hair - not a "ginger " gene and not a gene for extinction. FOXP1 gene associated with language , similar press misinterpretation that N could not talk. A curious story to do with canibalism and medical research. Cut marks from de-fleshing has left its traces on bones from as much as 600 kya , modern human and cut marks 70-80-90 kya , 14,000 years ago from Cheddar Gorge , all over the skull. Not necessarrily eating the body , maybe ritual respect de-fleshing . Genetics and the disease kuru in Papua New Guinea, E Highlands, in 1950s with the Foure speaking peoples , showed disease of violent shaking, loss of limb control , neuralogical problems, called the shaking disease, hysterical laughter - kuru a degenerate neurological condition . A genetic component to the disease , a prion disease like BSE , Scrapie,human CJD , and vCJD. Prions are proteins , attach themselves to brain and central nervous tissue , may have a function in transfer of trace element copper , between cells. At some point a prion will fold itself , sometimes a misfold, a dangerous form that affects all surrounding prions and they misfold also, killing living brain cells that are in contact with them. This ripple process produces plaquettes of dead brain cells. In a chromosome there are genes and on chr 20 at locus 129 has importance to prions , releasing amino acid that does things with the prions . When 2 mutations are the same , homozygosity, different pairs are heterozygosity. People in Papua with prion diseases , those surviving longest had the differing pair. Something to do with the prion folding process, prevented the continuation of the process across the brain. No cure but resistance was greater and incubation period was longer, some living 50 to 60 years with kuru and no symptoms. The homozygous people die and early manifestation. Birthyears of kuru infested areas, 2500 people dying 1940s to 1960s , about 1950 Oz took over, banning canabilism . Canabalism was part of mortuary rituals , mark of respect, taking on their power. Mostly carried out by women and young children. Males of 6 to 8 years removed from the women and placed in the male society. When plotted birthyear v amount of heterozygosity . For men line is around the mean . Women was larger than normal and drops with the ban and the natural defence of women drops as they dont need it as canibalism is becoming less important. A rise in the males at that time ,perhaps males born to those women of that time of 1950 onwards , then decades after the ban male and female plots both vary about the mean. Evolution and natural selection at work on humans , tracking an environmental problem , using an in built defence process , enhancing it , making it more common in the population , for those that survive all showing on a human generation timescale. World map of this gene pairing of alleles 129M and 129V, 2 of either and you are in trouble. Differing pair then you are better off . High homozygosity in Papua and low elsewhere around the world where there is not canibalism A sample of Q&A Q/ With kuru and that graphical plot there was a very noticeable change over as little as 10 years, how does evolution act so quickly. A change can be quick , a morphological change is much slower, but a gene change can be quick. Over single sperm and egg procreation event rather than over a generation. Q/ it is not syurvival of the fittest in that case if there is no choce of survive or not survive. Survival of the fittest is an older concept. Gene lineages can survive for long periods , sometimes because they are the best adapted . No change can predict what will happen , you can only deal with what you have available to you . Current phrasing would be is whatever your genome contains is what evolution will work on. Even Darwin in his first version of Origin, he used the phrase survival of the best adapted. Q/ How do children start to be being born with extra heterozygosity , wheras not being born with that variation before? What is the invisible force acting on the sperm or egg, we don't practise canabalism any more, so I can be born like this? Natural selection is an invisible filter within a population. Those who are homozygous will die more often . The heterozygous are living longer so their genetic pattern is put into the population more often , so more children are born with that state. Q/ The rate of change of mutation over time, you say, is constant ? That is an assumption that geneticists make. In MtDNA there is the situation where a mutation can revert back, with no known reason. How good the data is for a regular linear change process ? probably not as regular as geneticists say it is. Much easier when things are linear. Q/ Is there a possible lineage other than L ? All humans have L and L-mutations but possible there are others but unlikely Not all necessarily have survived, focusing now on only known survived genes. Q/ Any genetic indication that early humans were furred or non-furred? Non - furred, inferred;-), modern pattern of retaining some hair on the top of the head is a defence against the sun . Older balding men do not have much genetic history, they are dead before it goes into the next generation . Homo-erectus about 1.5m ya was the first hominym would be the first with recognisable modern human body plan. Of its thermo-regulatory apparatus , nose shape and position , much the same as us. Flow of blood around the head and down is in same direction as us today. From evidence of holes, through which veins would pass, is the same. First animal moving like a modern human, in the open and running quickly, - a thick furry pelt would inhibit such activity. Q/ Were global temperatures much the same? People think that with ice ages , you wake up one day and there are glaciers all around. But plenty of time to move and a cold winter and coolish summer now would not be that different to ice-age conditions when N were present , especially in areas of deep gorges and micro-climates. Q/ Could N adapt more easily to cold conditions ? They were less adaptable, tended to move less, becoming more isolated and gone to extinction. Hardy but not adaptable. No selective pressure on them for hundreds of thousands of years to adapt, as modern humans not around to do any forcing. Small nasal cavity and mid-facial region is pinched out associated with thermo-regulation and expelling of heat from the body. Q/ History of tatooing? N deposits have shown shells with pigment in them so could be used for tattoing or body decoration especially as N never painted caves. Q/ Any ochre associated with N burials Ochre on tools has been found but no defintive association with burials. Q/ Are there different races/peoples between hunter gatherers and farmers? Some genetic lineages appear at the time that farming begins , whether new people and new techniques - is possible. But must be some cross-over as the hunter-gatherer community would be around at the same time. So there would be confusion in the genetic signatures.

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