Ant What it Used to Be

first_imgA new species of subterranean ant discovered in Brazil is so weird, biologists have classified it as the sole representative of a new subfamily.  The alien creature has been whimsically named Martialis heureka: “the ant from Mars.”  An article about it in Nature News said, “It adds a new branch to the ant family tree which split off from the others extremely early in the family’s evolution.”  Trouble is, it doesn’t look anything like a wasp, from which ants supposedly evolved (see picture on National Geographic).    This has thrown ideas of ant evolution into a bit of a quandary.  Christian Rabeling, the discoverer, found that this ant did not fit into the existing taxonomy.  Scientists are calling this a relict species of a sister family they have named Martialis.  The original paper in PNAS says, “On the basis of morphological and phylogenetic evidence we suggest that these specialized subterranean predators are the sole surviving representatives of a highly divergent lineage that arose near the dawn of ant diversification and have persisted in ecologically stable environments like tropical soils over great spans of time.”  That makes it essentially a living fossil.  “Like the duck-billed platypus is to mammals,” explained Nature News, “it’s clearly a cousin to other ants, yet a weird and ancestral version that took its own evolutionary direction early on.”  This must be what the title of the paper means when it says the discovery “sheds light on early ant evolution.”    A look inside the paper, though, reveals a few problems with the confident assertions about evolution:A robust phylogeny is indispensable for elucidating the evolutionary origin of ants and for exploring the selective forces that have produced their extraordinary specializations.  Previously published studies, however, led to contradicting views of early ant evolution, in part because of high levels of morphological convergence, the secondary loss of characters, and a lack of informative paleontological data.  As a result, numerous taxa have been proposed as the most basal lineage.Recent attempts to find a robust phylogeny have now been dealt another challenge with the discovery of M. heureka.  Their phylogenetic tree shows it on its own branch, all by itself.  Another problem is revealed deep in the paper: “Second, the basal ant lineages seem to have originated in a relatively short period, potentially making the unambiguous resolution of their relationships quite difficult and sensitive to methodological error.”  The only suggestion of light being shed on ant evolution by this discovery is that it turns their attention away from the idea ants evolved from wasps.  What they expected, and what they found, were pointing in opposite ways:Our phylogenetic analyses, combined with the inferred biology of M.  heureka, suggest that the most basal extant ant lineages are cryptic, hypogaeic foragers, rather than wasp-like, epigaeic foragers (Fig. 3).  This finding is congruent with recent molecular studies, which previously suggested the Leptanillinae, another subfamily of subterranean predators, to be sister lineage to all extant ants.  This result has puzzled ant systematists for two reasons.  First, Wilson et al.’s classic study of the Mesozoic amber ant Sphecomyrma postulated that the ancestral ant was a large-eyed, wasp-like, ground forager, creating a strong expectation that the most basal extant ant lineages would also be epigaeic foragers, presumably similar to Sphecomyrma.  Second, the Leptanillinae [blind foragers in Africa] share common morphological and behavioral characteristics with the Amblyoponinae, implying the monophyly of this group.  In contrast, our results and recent molecular systematic studies suggest that blind, subterranean, specialized predators, like Martialis, the Leptanillinae, and some poneroids, evolved early during ant diversification.  We hypothesize, that once these hypogaeic predators adapted to their specialized subterranean environment, their morphology and biology changed little over evolutionary time because their hypogaeic habitat has likely been ecologically stable and provided a refuge from competition with other, more recently evolved, ants.  It is important to note that no definitive statement about the morphology and life history of the ancestral, Mesozoic ant can be derived from our current knowledge about the surviving basalmost ant lineages, because the relative probabilities of evolutionary transitions between epigaeic and hypogaeic habits are uncertain.They explained that the supposition that ants evolved from wasps relies on ambiguous data subject to alternative hypotheses.  One other problem with their suggestion that ants evolved from wasps is that Martialis would make the ant hypogaeic [underground] foraging evolve three times.  That’s why they are suggesting the basal ant was already a hypogaeic forager.  “The exact nature of the ancestral ant remains uncertain,” though, “given that the propensity for repeated evolution of a hypogaeic lifestyle may be higher than for reevolution of an epigaeic lifestyle.”    In short, no clear light seems to have been shed on ant evolution by this discovery.  It was a complete surprise.  What other surprises lie in store?  “This discovery hints at a wealth of species, possibly of great evolutionary importance, still hidden in the soils of the remaining rainforests.”    Stefan Cover, a curatorial assistant at Harvard’s Museum of Comparative Zoology, had a more humble view.  In the Nature News article, he said that Martialis “jars us out of going with our familiar conceptions… This is a lesson that we could probably import into studies of other groups.”1.  Rabeling, Brown and Verhaugh, “Newly discovered sister lineage sheds light on early ant evolution,” Proceedings of the National Academy of Sciences USA, published online before print September 15, 2008, doi: 10.1073/pnas.0806187105.We can suggest some other studies of other groups where evolutionists could import this lesson: how about the Monera, Protista, Fungi, Plantae and Animalia? (the five kingdoms of taxonomy).    The discoverers put their weird little ant in a jar, but maybe the scientists need to be put in one, because Martialis “jars us out of going with our familiar conceptions,” Cover said.  While they’re safely in a jar out of harm’s way (unable to harm us, that is), let’s hunt for more rainforest species with great evolutionary importance.  Jarring evolutionists is fun.  Every new discovery jars them into realizing their neat little schemes are wrong.  They’re like blind hypogaeic foragers, digging around in their own dirt, thinking every new surprise is shedding light on evolution.    That phrase – “Shed[ding] light on evolution” – yields thousands of hits on Google.  We’ve examined dozens of those claims right here.  Can you remember one that has turned up a single photon?  The truth is they are walking in a darkness of their own making.  The light they need to see is the flashing red stop light next to the “Wrong Way” sign they missed back in 1859.(Visited 14 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

Housing projects to curb SA slums

first_imgA complex part of the Emerald Sky project in East London.(Image: Social Housing Company) The Kliptown Housing Project in Soweto is part of government’s social housing programme. (Image: Bongani Nkosi) MEDIA CONTACTS • Chris Vick Department of Human Settlements Spokesperson +27 83 556 7644 or +27 12 421 1645 RELATED ARTICLES • Zuma’s 2010 plan of action • Social development in South Africa • Govt launches massive ID drive • First university for MpumalangaBongani NkosiGovernment has vowed to curb the proliferation of informal settlements in South Africa’s cities, with more social housing projects set to roll out in 2010.President Jacob Zuma launched the latest such project, the Emerald Sky human settlements project, in East London in the Eastern Cape on 19 June. It is described as an “innovative housing project” with 656 duplex-styled units, 350 of which are already occupied.“The Emerald Sky project is one of many that will be launched to provide affordable housing to people in need,” said Zuma. “Many will be launched around the country during the year.”Emerald Sky is part of government’s social housing programme and aims to provide decent rental houses for low and middle income earners. These are generally South Africans whose salaries are too high to get direct government subsidies, but earn too little to qualify for a bank mortgage.Government is providing grant funding to private companies to build the rental homes in a bid to curb the growth of slums.The primary aim is to ensure that low and middle income workers, looking for affordable rent, are able to live in decent houses nearer to their workplaces. It is also about keeping them closer to facilities such as hospitals, schools and shopping centres.Emerald Sky is close to East London’s industrial areas of Wilsonia and Braelyn, and sits within a 5km radius of Frere Hospital and educational facilities.“You will notice that the new style social housing projects that we are building are on well-located and landscaped land,” Zuma said. “They ensure proximity to economic opportunities, transport and urban centres.“The settlements also contribute to our social transformation programme of reversing apartheid spatial planning and to restore the human dignity and self-esteem of our people.”8 000 human settlement projects Government is currently involved in more than 8 000 housing projects across the country, according to Zuma. It’s also upgrading most of the 2 700 informal settlements that “exist alongside almost every urban and peri-urban town, to address the squalid conditions of those living there”.The government-run Guarantee Fund makes it easier for working-class people to access a mortgage bond to build their own homes. It aims to eliminate stumbling blocks that face some South Africans when applying for funding at banks and other financial institutions.The Department of Human Settlements, headed by former businessman Tokyo Sexwale, was allocated R15-billion (US$2-billion) to spend on housing this year.Government has been behind numerous social housing projects in different communities. Since 1994 it has built over 2.7-million homes, both rental and fully subsidised. “In doing so, more than 13-million people have been provided with adequate shelter,” Zuma said.Some of the free housing projects, known as Reconstruction and Development Programmes (RDPs), have been marred by shoddy workmanship, while others have not met inhabitable standards or have been left unfinished. Sexwale lashed out at companies involved in such projects and announced that his department will spend R300-million ($40-million) to repair poorly-built RDP houses.last_img read more

Wear slippers to help make dreams come true

first_imgYoung girls smile, enjoying last year’s successful Reach for dream Slipper Day. (Image: Reach for a Dream)For one day people can swap stilettos, brogues or sneakers for cosy slippers in the name of helping a gravely ill child.Reach for a Dream Foundation’s Slipper Day calls on ordinary citizens to make a difference by just donating R10 for a sticker to allow people to go to work on 5 August 2016 wearing slippers.This nationwide campaign has grown quickly since its inception in 2011. At first it was a provincial campaign when it amassed R175 000 in KwaZulu-Natal. In 2012 it went national and managed to raise R1.3-million. In 2015 it collected a staggering R3.5-million.According to Reach for a Dream’s website Slipper Day is a “fun initiative that creates awareness for the foundation, whilst raising funds to make more dreams a reality for children fighting life-threatening illnesses”.Bronwyn Feldwick-Davis, the foundation’s marketing manager said Slipper Day is successful because it gets all South Africans involved for as little as R10.“The thought of a child battling for their life when they should be enjoying the most magical time of their lives, their childhood, is something that most citizens feel compassion and empathy towards.”Julia Sotirianakos, CEO at the foundation said Slipper Day provides people an easy way to do something good and support children fighting life-threatening illnesses.“Even during tough economic times you can make a difference with just R10 and doing something fun with your feet,” she said.“By wearing your slippers on Slipper Day, you can help to bring dreams to life and if we can make dreams come true, we can instil hope in a child which will help them to continue fighting.”This year the foundation hopes to sell 650 000 stickers, which will almost double its fundraising total from 2015.Stickers can be bought at Reach for a Dream branches, as well as in Wimpy or Pick ‘n Pay stores nationwide.Reach for a Dream has been helping children and teens battling life-threatening illnesses since 1988. Whether it’s a surprise birthday party, a laptop, shopping sprees or meeting their favourite personality, the foundation has been making dreams come true.last_img read more

Urban Rustic: Air Sealing the Exterior Sheathing

first_imgAll About Water-Resistive BarriersA New Encyclopedia Article on Water-Resistive BarriersWhat’s New with Water-Resistive BarriersWall Sheathing OptionsZip Sheathing TipsReturn to the Backyard Tape TestAir-Sealing Tapes and GasketsLiquid-Applied Flashing Editor’s note: This post is one of a series by Eric Whetzel about the design and construction of his house in Palatine, Illinois, a suburb of Chicago. The first blog in his series was called An Introduction to a New Passive House Project; a list of Eric’s previous posts appears below. For more details, see Eric’s blog, Kimchi & Kraut. Fixing misaligned seamsOnce the Zip sheathing was fully installed, it became readily apparent that some of the seams, especially near the base of the first floor where a horizontal seam ran around the entire structure, were out of alignment and would need some adjustment (see Image #2, below). This seemed to be a problem in areas between studs.Using a 1×4 in each stud bay, I was able to pull the seam together. It wasn’t always perfect, but the improvement was visibly significant and in most areas well worth the effort. After placing a length of 1×4 into position over the seam on the inside (see Image #3 below), I drove a couple of screws from the inside to the exterior to hold the board in place.With the 1×4 securely attached from the interior, I went outside and drove several screws into the sheathing, both above and below the seam, to bring the two sections of sheathing into alignment. At that point, I could go back inside and remove the two screws that had been driven towards the exterior. Keeping track of air barrier penetrationsBefore construction began, I made a mock wall assembly (see Image #5 below). This proved helpful when explaining to the various subs how to help me protect the air barrier — especially when it came time to drill holes through the Zip sheathing. Of particular importance was locating any holes closer to the center of a stud bay, as opposed to hugging a corner or side of one of the 2×6 framing members. A hole cut too close to a stud or a roof truss is much harder to air seal properly.Our original plumber was the only trade contractor that managed to screw this up. (It’s no coincidence that he was also the only sub that we had to fire.)In effect, any time a sub had to make a penetration through the air barrier we discussed the details, and once the cut was made I immediately air sealed the penetration both on the exterior and interior.By sealing each hole in the sheathing on both sides, I hope to ensure the long-term durability of the structure. The main argument for this strategy assumes that the exterior side of the sheathing will face more extreme temperatures and fluctuations in humidity, and presumably even wind-driven rain if and when it gets past the siding and 4 inches of Roxul insulation. By taking the time to seal the interior side, it just gives the overall air barrier, and therefore the structure, a better chance at avoiding air and water intrusion. That’s the goal, anyway.For air sealing I used a mix of tapes, HF sealant (later, even some Prosoco products), EPDM Roflex gaskets, and duct seal.The penetrations for the electric service were my first go at using the Roflex gaskets (see Image #6 below). The smaller diameter Roflex gasket comes with its own Tescon Vana tape, which makes installation straightforward. See Images #7 and #8 below for interior and exterior views of sealed penetrations.It was a big moment when the electric panel went in. The house is ready for power. We used Zip System sheathing as our water-resistive barrier (WRB), sometimes called a weather-resistant barrier, based largely on Hammer & Hand projects we had seen and various jobs featured in Fine Homebuilding magazine.As the 7/16-inch Zip sheathing went up, I taped most of the seams with Pro Clima’s 3-inch Tescon Vana tape (available at 475 High Performance Building Supply) as well as 6-inch Contega tape, which I used mainly for outside corners.My wife and daughter also cut up Tescon Vana into small pieces in order to cover all the nail and screw holes in the sheathing. Initially, the nail holes had been sealed with Contega HF sealant, also available from 475, thus giving these penetrations double coverage. BLOGS BY ERIC WHETZEL Installing a Solar Electric SystemPrepping for a Basement SlabBuilding a Service CoreAir Sealing the Attic FloorVentilation BafflesUp on the RoofA Light Down BelowKneewalls, Subfloor, and Exterior WallsLet the Framing BeginDetails for an Insulated FoundationThe Cedar Siding Is Here — Let’s Burn It An Introduction to a New Passive House Projectcenter_img The green skin of the sheathing held up nicely during construction, even as it sat exposed for nearly 10 months after we fired our GCs and struggled to keep the project moving forward. Nevertheless, it is little more than glorified OSB, which comes with certain inherent weaknesses.Matt Risinger does an excellent job of delineating the costs and benefits of using either OSB or CDX plywood as a sheathing material in this video. And if you’re interested in a video about how WRBs have evolved over time you might enjoy this one, which features Joe Lstiburek of Building Science Corporation. Many WRB options are availableIf I had it to do over, I think I might be tempted to use 1/2-inch exterior grade plywood as my sheathing; there are many WRB options these days. The plywood could be sealed on the exterior side with either a liquid membrane, such as Prosoco’s Cat 5, or a peel-and-stick membrane like Henry’s Blue Skin, or even another 475 product, Solitex Mento 1000. Air-sealing on the insideIn addition to air sealing the exterior side of the Zip sheathing, I also invested some time in air-sealing the interior side of the Zip sheathing as well (see Image #4 below).Sealing on the interior side with HF Sealant, even between vertical framing members, means that even if there are any weaknesses in either the Zip sheathing or the Tescon Vana tape at these points, air won’t find an easy way in, since it will be blocked from the interior side as well. (There won’t be a difference in air pressure to help the outdoor air make its way indoors.)I held off on using the sealant at the connection between the wall sill plate and the subfloor until just prior to installing the Intello membrane on the walls since this area constantly attracts dirt and debris.This kind of redundancy in air sealing should give the house long-term protection against air leaks, thereby aiding the durability of the structure, as well as making it a much more comfortable environment to live in. RELATED ARTICLES last_img read more

New Jersey Police Now Need Warrants To Track Cellphones

first_imgWhat it Takes to Build a Highly Secure FinTech … readwrite Related Posts Role of Mobile App Analytics In-App Engagement Tags:#GPS#law#Location#now#smartphones#surveillance center_img Why IoT Apps are Eating Device Interfaces The New Jersey Supreme Court ruled Thursday that police must obtain a warrant prior to pulling cellphone location data. The ruling makes New Jersey only the second state (after Montana) to require police to show probable cause to a judge before they can request location data from cellphone carriers. While the ruling won’t have any immediate impact outside of New Jersey, it could indirectly influence other courts wrestling with the balance between effective law enforcement and personal privacy. Lower courts remain divided on the subject, suggesting that the issue may eventually be resolved by the Supreme Court.Image via Shutterstock The Rise and Rise of Mobile Payment Technologylast_img read more

Neutral Density Filter Shootout – Which ND Filter is Best?

first_imgPolariod ND fader FilterGenus ND fader FilterLightcraft Fader ND Mark IITiffen Variable NDSingh-Ray Vari-ND FilterHeliopan 77mm Variable ND FilterWhat is a neutral density filter?For those unfamiliar, a neutral density filter is a glass filter that you affix to the end of a camera lens.  The filter modifies light intensity, which gives a photographer or DSLR video shooter more flexibility in their shot, with the ability to use a larger aperture.  Neutral density (or ND) filters range in price and quality/effectiveness.  Dave tested the ND filters for the following factors:SharpnessBokehColor CastSee which ND filter Dave named a best bet based on quality and cost.  For anyone looking to purchase or learn more about professional grade ND filters, this video is a must watch: Looking to buy an ND filter?  Be sure to check out this video review.  6 popular ND filters go head-to-head and one is chosen as a best buy for pro photographers and DSLR shooters.LearningDSLRVideo.com’s Dave Dugdale recently completed a thororgh test on 6 commercial neutral dentisty filters for photographers and DSLR shooters.  The real world test of these filters included the following brands and models:last_img read more