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"The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations. Considerable variation exists in the evolved multicellular life cycles, with both cell number and propagule size varying among isolates. Survival assays show that evolved multicellular traits provide effective protection against predation. These results support the hypothesis that selection imposed by predators may have played a role in some origins of multicellularity."

"No country in the world currently meets the basic needs of its citizens at a globally sustainable level of resource use. Our research, recently published in Nature Sustainability (and summarised in The Conversation), is the first to quantify the national resource use associated with achieving a good life for over 150 countries. It shows that meeting the basic needs of all people on the planet would result in humanity transgressing multiple environmental limits, based on current relationships between resource use and human well-being. The chart below demonstrates the profound challenge nations currently face. National performance on seven environmental sustainability indicators is plotted against eleven minimum social thresholds for a good life (see About page for further details). Ideally, nations would be located in the top-left corner with no biophysical boundaries transgressed and all minimum social thresholds achieved."

"Carbon dioxide (CO2) is a gas essential for life- animals exhale it, plants sequester it. It exists in Earth's atmosphere in comparably small concentrations, but is vital for sustaining life. CO2 is termed a greenhouse gas (GHG) - a gas which absorbs and emits thermal radiation creating the 'greenhouse effect'. Along with other greenhouse gases, such as nitrous oxide and methane, CO2 is important in sustaining a habitable temperature for the planet: if there were absolutely no GHGs, our planet would be simply too cold. It has been estimated that without these gases, the average surface temperature of the Earth would be about -18 degrees celcius.1 Since the Industrial Revolution, however, energy-driven consumption of fossil fuels has led to a rapid increase in emissions of CO2, disrupting the global carbon cycle and leading to a planetary warming impact. As an international community, UN member parties have set a target of limiting average warming to 2 degrees celcius above pre-Industrial temperatures."

1. The Primordial Soup 2. Deep-Sea Vents 3. Panspermia 4. The Deep-Hot Biosphere Theory 5. The Radioactive Beach Hypothesis

"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"Back in the 1980s, a group of social workers in Jamaica visited low-income homes one hour a week for two years, bearing age-appropriate toys for the kids and advice on child rearing for the parents. Researchers tracked the outcomes, and a generation later, the results are in. The children whose homes were visited by social workers became adults who earn wages that are 25 percent higher than those earned by peers who had not been visited. Their I.Q.s are an average seven points higher, and they are less likely to resort to crime or suffer from depression. Other studies, including several recent ones in the United States, have shown similar results, contributing to a consensus on the importance of early childhood development that has led governments around the world to increase spending on the first five years of life. In Latin America and the Caribbean, a region of longstanding social and economic inequality, several countries have been especially ambitious. Brazil and Chile doubled the coverage of day care services over the past decade, while in Ecuador they grew sixfold. These investments build on historic gains in child nutrition and health. But while Latin American children are now healthier and more likely to attend preschool, they still lag far behind in learning, particularly in the areas of language and cognition, when compared with their counterparts in wealthy countries. What are we doing wrong? ..."

Social Media, Social Life: How teens view their digital lives

"Max Roser (2016) - 'World Poverty'. Published online at OurWorldInData.org. Retrieved from: http://ourworldindata.org/data/growth-and-distribution-of-prosperity/world-poverty/ In the past only a small elite lived a life without poverty. Since the onset of industrialization - and as a consequence of this, economic growth1 - the share of people living in poverty started decreasing and has kept on falling ever since. But as a consequence of falling poverty, the health of the population improved dramatically over the last two centuries, and the population started to grow.2 The growth of the population caused the absolute number of poor people in the world to increase; only recently has the absolute number of people living in poverty started to fall as well. This data entry chronicles the falling poverty over the last centuries."

Las 3 reglas de @ramusallam: 1 la curiosidad va primero 2 aceptar el desastre 3 practicar la reflexión "It took a life-threatening condition to jolt chemistry teacher Ramsey Musallam out of ten years of "pseudo-teaching" to understand the true role of the educator: to cultivate curiosity. In a fun and personal talk, Musallam gives 3 rules to spark imagination and learning, and get students excited about how the world works. "

"It seems only fitting to explore the role of questions in education by asking questions about the process of doing so. I propose that we start with the customary way of framing this topic and then proceed to questions that are deeper and potentially more subversive of traditional schooling. 1. WHICH QUESTIONS? To begin, let's consider what we might ask our students. The least interesting questions are those with straightforward factual answers. That's why a number of writers have encouraged the use of questions described variously as "true" (Wolf, 1987), "essential" (Simon, 2002), "generative" (Perkins, 1992; Perrone, 1998), "guiding" (Traver, 1998), or "fertile" (Harpaz & Lefstein, 2000). What the best of these share is that they're open-ended. Sometimes, in fact, no definitive right answer can be found at all. And even when there is one - or at least when there is reason to prefer some responses to others - the answer isn't obvious and can't be summarized in a sentence. Why is it so hard to find a cure for cancer? Do numbers ever end? Why do people lie? Why did we invade Vietnam? Grappling with meaty questions like these (which were among those generated by a class in Plainview, NY) is a real project . . . literally. A question-based approach to teaching tends to shade into learning that is problem- (Delisle, 1997) and project-based (Kilpatrick, 1918; Blumenfeld et al., 1991; Wolk, 1998). Intellectual proficiency is strengthened as students figure out how to do justice to a rich question. As they investigate and come to understand important ideas more fully, new questions arise along with better ways of asking them, and the learning spirals upwards. Guiding students through this process is not a technique that can be stapled onto our existing pedagogy, nor is it something that teachers can be trained to master during an in-service day. What's required is a continual focus on creating a classroom that is about thinking rather

"This book YOUNG & CREATIVE - Digital Technologies Empowering Children in Everyday Life aims to catch different examples where children and youth have been active and creative by their own initiative, driven by intrinsic motivation, personal interests and peer relations. We want to show the opportunities of digital technologies for creative processes of children and young people. The access to digital technology and its growing convergence has allowed young people to experiment active roles as cultural producers. Participation becomes a keyword when "consumers take media into their own hands". Digital technologies offer the potential of different forms of participatory media culture, and finally creative practices. YOUNG and CREATIVE is a mix of research articles, interviews and case studies. The target audience of this book is students, professionals and researchers working in the field of education, communication, children and youth studies, new literacy studies and media and information literacy."

"Because energy fuels both human development and environmental damage, policies that encourage energy demand reduction can run counter to policies for alleviating poverty, and the other way around. Achieving both objectives can only happen if energy use is spread more equally across societies. However, while it's widely acknowledged that part of the global population is living in 'energy poverty', there's little attention given to the opposite condition, namely 'energy excess' or 'energy decadence'. Researchers have calculated minimum levels of energy use needed to live a decent life, but what about maximum levels? "

"As I've pointed out previously, I doubt there will be a human on Earth by mid-2026. Indeed, I doubt there will be complex life on this planet by then. It'll be a small world, as was the case in the wake of each of the five prior Mass Extinction events on Earth. Bacteria, fungi, and microbes will dominate."

"1- CrashCourse 2- Unboxing philosophy 3- Complexus 4- La ronda filosófica 5- The School of Life ¡Yapa!: Vlog de Filosofía"

""Every action and decision we take - or don't - ripples into the future. For the first time we have the capability, the technology, and the knowledge to direct these ripples." Jacque Fresco Music: Protect Life, Human Nature, Koolen, Leelo - Eric Serra"

Hasta donde pude ver funciona muy bien, incluso el audio generado en castellano... bastante poderosa, habrá que ver hasta cuándo es gratis su uso... "Edit video as easily as editing text! Do you need to create videos from images, audio files, video clips or screen grabs? Save yourself a lot of headaches by giving all of the painful parts to Video Puppet. Video Puppet will automatically create video clips from images, align audio and video segments, add captions, and even create a life-like narration audio from your text. To top it off, you'll be able to update the video easily when your content changes."

"The Kaua Moho was the last species of it's entire genus and it was the last genus in it's family. This male was not just the last of his kind, he was the last being on his entire branch of the evolutionary tree, there was nothing left on the planet that was even close to being like him. That kind of loneliness is unimaginable. No other avian family has had every single species within it go completely extinct in modern times. Different species of Moho lived on each island of Hawaii and their evolutionary cousins the kioea birds lived alongside them, but starting in 1800 (about the time Europeans started arriving to the islands in significant numbers and also about the time the native human population of Hawaii also got decimated by diseases) one by one they died out due to the introduction of foreign avian diseases and parasites, habitat loss, and hunting for their plumage. 2 hurricanes within 10 years of each other finished them off. They are all gone and that song or any song like it will never be heard again save for in recordings. The hurricanes dealt the final blow, but 95% of it was humanity's fault. This has become common in Hawaii due to having so many species that only exist there. A LOT of those species are gone now because the arrival of Europeans brought disease, invasive species, and people straight up killed them or destroyed their habitats. It is a similar situation on every isolated island or area in the world as humans have expanded and explored every nook and cranny on the planet, no matter how hard it is to get to or how little business we have there we feel the need to interfere in even the most delicate and tiny ecosystem. Even the large, continent sized ecosystems are suffering. It doesn't matter if there are millions or even billions of an animal or plant, we will find some way to kill them all. It is only in the last few decades that serious steps have finally been taken to preserve the few areas on this world that we have not destroyed, but

"Hardly anyone seems to have noticed that the newest climate science suggests we are about to pass the point of no return, to unstoppable, catastrophic global warming. This short animation explains the positive feedback mechanisms that mean the Earth's climate system has a tipping point, followed by a brief glimpse into the crystal ball of horrors that will almost certainly come to pass if we cross it. Finally, the film explores how we got into the mess we're in, and the possibilities still open to us to prevent the worst natural and humanitarian disaster in human history, and the very real possibility of the end of civilization, and of life as we know it."

"Me pareció interesante indagar a qué edad escribieron sus obras clave algunos novelistas de renombre. Entre la curiosidad, el asombro y la autoflagelación comparativa, terminé haciendo un relevamiento de 130 obras. Mi selección es, por supuesto, arbitraria. Son novelas que me gustaron o me interesaron (en el caso de haberlas leído) o que -por distintos motivos y referencias, a veces algo inasibles- las considero importantes (aunque no las haya leído todavía)."

En inglés publica numerosos informes sobre TICs, uso de la tecnología....