What is Natural Selection?

This episode of State Clearly was only possible with support from our viewers, and from Brain-Tools.org a company dedicated to developing and delivering to patients, new treatments for Alzheimer's. Stated Clearly presents: What is Natural Selection? Natural selection is one of several key concepts contained within the theory of evolution. To understand exactly what natural selection is and why it's so important let's first take a quick look at two other evolutionary concepts: Descent with Modification and the overarching idea of Common Descent. Descent with Modification is the observable fact that when parents have children, those children often look and behave slightly different than their parents, and slightly different than each other. They descend from their parents with modifications. The differences found in offspring are partially due to random genetic mutations.

Common Descent is the idea that all life on Earth is related. We descended from a common ancestor. through the gradual process of descent with modification over many many generations, a single original species is thought to have given rise to all the life we see today. the common descent of all life on earth is not a directly observable fact. We have no way of going back in time to watch it happen. Instead, Common Descent as a conclusion based on a massive collection of observable facts. Facts found independently in the study of fossils genetics comparative anatomy mathematics biochemistry and species distribution. Because the evidence for common descent is so overwhelming, the concept has been around since ancient times. In the past however, it was rejected by many philosophers and scientists for one main reason: You cannot get order and complexity from random chaos alone. The bodies and behaviors of living things are extremely complex and orderly.

Descent with Modification simply produces random variation. All through history no one could explain how complex life arose from simple life through random variation, until Charles Darwin discovered Natural Selection. Charles Darwin, who lived from 1809 to 1882 was a naturalist: someone who studies nature. At the start of his career he traveled the world by ship, collecting and documenting plants and animals. During his travels, Darwin became very interested in the idea of common descent. He noticed that islands contain species of plants and animals unique to those islands, they can't be found anyplace else on earth, but they often look and behave surprisingly similar to creatures found on nearby continents.

Tortoises on the Galapagos islands can be distinguished from those of Africa, meanwhile, with the exception of size, they're almost identical to a species found nearby in South America. Darwin believed the similarities could be best explained through Common Descent. Long ago a tortoise from the mainland may have drifted to the islands, possibly on a raft of storm debris, and once arriving, laid her eggs. Random changes caused by Descent with Modification over thousands of years, eventually transformed the island creatures and the mainland creatures so much, that they could no longer be considered the same species. This idea made good sense to Darwin except for one thing: the island creatures he found were not just randomly different from their mainland cousins, they were specially adapted for island life. the Galapagos is a collection of 18 main islands, many of which are home to tortoises.

The larger islands have lots of grass and vegetation. Tortoises there grow extra heavy and have dome like shells. Some of the smaller islands have very little grass, forcing the tortoises to feed on island cactus. the best cactus pads grown the tops of these plants. Fortunately, tortoises on these islands are equipped with expanded front legs and saddle like shells allowing them to stretch their necks extra long to reach their food. It's almost as if these island creatures have been perfectly sculpted to survive within their unique environments. How did this sculpting take place? Random Descent with modification alone could never do such a thing. Darwin drew upon his knowledge of selective breeding to answer this question. For thousands of years, farmers have been taking wild plants and animals, and through the process of selective breeding, have sculpted the original wild forms into new domestic forms, much better suited for human use and consumption. The process is slow but simple if a single plant produces a hundred seeds, most will grow to be nearly identical to the parent plant.

A few however, will be slightly different. Some variations are undesirable: smaller size, bitter taste, vulnerability to disease and so on. Other variations are highly valued! Thicker sweeter leaves for example. If a farmer only allows the best plants to reproduce and creates seeds for the next crop, small positive changes will add up over multiple generations, eventually producing a dramatically superior vegetable. You might be surprised to hear that broccoli cauliflower, kale, brussels sprouts, and cabbages, are all just different breeds of a single type of weed commonly found along the shores of the English Channel. The evolution of this original plant into all the varieties we see today was carefully guided by different farmers around the world, who simply selected for different traits. It's important to note, that the farmer doesn't actually create anything. Random Descent with Modification creates new traits. The farmer simply chooses which of those new creations are allowed to reproduce, and which are not. Darwin proposed that nature itself is also capable of selection.

It may not have an intelligent brain like a farmer, but nature is an extremely dangerous place in which to live. There are germs which can kill you. Animals that can eat you. You could die of heat exhaustion. You could die of exposure to the cold. When parents produce a variety of offspring, nature, simply by being difficult to survive in, decides which of those variations get to live in reproduce, and which do not. Over multiple generations, creatures became more and more fit for survival and reproduction within their specific environments. Darwin called this process Natural Selection. Since Darwin first put forth his idea in the mid 1800s Natural Selection has been studied and witnessed numerous times in nature and in the science lab. What started out as a mere idea is now officially an observable fact! Darwin's discovery has greatly expanded our understanding of the natural world it has lead to amazing new breakthroughs, and it finally allowed scientists to seriously consider the idea of Common Descent.

So to sum things up, What exactly is natural selection? Natural Selection is the process by which random evolutionary changes are selected for by nature in a consistent orderly non random way. Through the process of descent with modification, new traits are randomly produced. Nature then carefully decides which of those new traits to keep. Positive changes add up over multiple generations, negative traits are quickly discarded. Through this simple ongoing process, nature, even though it may not have a thinking mind, is capable of producing incredibly complex and beautiful creations. I'm Jon Perry, and that's Natural Selection stated clearly! that's it for this episode if you enjoyed it, subscribe to us on youtube and follow us on out face book page. if needed, I can be contacted directly from our website at statedclearly.com .

Ocean Seeding – A New Technology that can Save Marine Life

People have relied on the abundance of the ocean since the beginning of human history. But things are rapidly changing. Scientists project that by 2048 the ocean will be depleted and fisheries will cease to exist. Billions of people rely on fish as their primary source of food and income – a number that will continue to grow over the next few decades as the world population increases. A collapse of ocean fisheries will be a massive threat to the food security and well-being of life on this planet. Nations around the world are pursuing better management practices and sustainable fishing in an attempt to curb this loss… but it is not enough. Despite our efforts, the health of the ocean is decaying even faster than initially predicted. Moreover, we have discovered that overfishing is only part of the problem. To see the bigger picture, we have to go much, much smaller. The whole oceanic ecosystem obtains its energy, food, and nutrients from tiny green phytoplankton – microscopic organisms that play a critical role as the base of the marine food chain. They grow and multiply through the absorption of sunlight – alongside water, carbon dioxide, and micronutrients such as iron.

Phytoplankton are the food of zooplankton, which in turn are consumed by small fish, which are themselves consumed by larger ones and so on. For their health, phytoplankton depend on the natural fertilization of iron-rich winds and upwelling currents, which have been ongoing for millions of years. However, as a result of climate change, winds and currents are changing, and the oceans are getting warmer. This hinders the mixing of surface layers, separating phytoplankton from the nutrients they need to grow. A NASA study has shown a constant decrease of phytoplankton in the ocean… 1% per year since 1950. That means plankton has declined more than 40% in just 60 years. When phytoplankton are in danger, the whole ocean is in danger. Less plankton means less food for fish and other organisms. With the continual decline of plankton, we are facing the collapse of the marine food chain as we know it due to climate change.

The question is: WHAT CAN BE DONE? Over the last several decades, scientists have observed that the iron-rich dust of volcanic eruptions can create massive plankton blooms over deserted areas of the ocean. On several occasions, scientists saw the volume of wild fish in these areas increase significantly – far beyond expectations. Given these observations, experts began to consider what might happen if humans could mimic natural volcanic iron fertilization to boost ocean life. This process is known as OCEAN SEEDING. In a recent Ocean Seeding project, researchers added iron dust to an area of the ocean that was part of the migratory route of juvenile salmon. Only a year later, mainland rivers experienced one of the largest salmon returns in history. Ocean Seeding offers an opportunity to begin repairing the damage to our ocean, rebuild wild fish stock, and improve food security for the growing populations of the world. This vital shift cannot be made without further research in Ocean Seeding and your support. Support us by sharing this video with your friends on social media.

And join the conversation on Twitter with hashtag #OceanSeeding.

Dan Barber: How I fell in love with a fish

So, I've known a lot of fish in my life. I've loved only two. That first one, it was more like a passionate affair. It was a beautiful fish: flavorful, textured, meaty, a bestseller on the menu. What a fish. (Laughter) Even better, it was farm-raised to the supposed highest standards of sustainability. So you could feel good about selling it. I was in a relationship with this beauty for several months. One day, the head of the company called and asked if I'd speak at an event about the farm's sustainability. "Absolutely," I said. Here was a company trying to solve what's become this unimaginable problem for us chefs: How do we keep fish on our menus? For the past 50 years, we've been fishing the seas like we clear-cut forests. It's hard to overstate the destruction.

Ninety percent of large fish, the ones we love — the tunas, the halibuts, the salmons, swordfish — they've collapsed. There's almost nothing left. So, for better or for worse, aquaculture, fish farming, is going to be a part of our future. A lot of arguments against it: Fish farms pollute — most of them do anyway — and they're inefficient. Take tuna, a major drawback. It's got a feed conversion ratio of 15 to one. That means it takes fifteen pounds of wild fish to get you one pound of farm tuna. Not very sustainable. It doesn't taste very good either. So here, finally, was a company trying to do it right. I wanted to support them. The day before the event, I called the head of P.R. for the company. Let's call him Don. "Don," I said, "just to get the facts straight, you guys are famous for farming so far out to sea, you don't pollute." "That's right," he said. "We're so far out, the waste from our fish gets distributed, not concentrated." And then he added, "We're basically a world unto ourselves.

That feed conversion ratio? 2.5 to one," he said. "Best in the business." 2.5 to one, great. "2.5 what? What are you feeding?" "Sustainable proteins," he said. "Great," I said. Got off the phone. And that night, I was lying in bed, and I thought: What the hell is a sustainable protein? (Laughter) So the next day, just before the event, I called Don. I said, "Don, what are some examples of sustainable proteins?" He said he didn't know. He would ask around. Well, I got on the phone with a few people in the company; no one could give me a straight answer until finally, I got on the phone with the head biologist. Let's call him Don too. (Laughter) "Don," I said, "what are some examples of sustainable proteins?" Well, he mentioned some algaes and some fish meals, and then he said chicken pellets. I said, "Chicken pellets?" He said, "Yeah, feathers, skin, bone meal, scraps, dried and processed into feed." I said, "What percentage of your feed is chicken?" Thinking, you know, two percent.

"Well, it's about 30 percent," he said. I said, "Don, what's sustainable about feeding chicken to fish?" (Laughter) There was a long pause on the line, and he said, "There's just too much chicken in the world." (Laughter) I fell out of love with this fish. (Laughter) No, not because I'm some self-righteous, goody-two shoes foodie. I actually am. (Laughter) No, I actually fell out of love with this fish because, I swear to God, after that conversation, the fish tasted like chicken. (Laughter) This second fish, it's a different kind of love story. It's the romantic kind, the kind where the more you get to know your fish, you love the fish. I first ate it at a restaurant in southern Spain. A journalist friend had been talking about this fish for a long time. She kind of set us up.

(Laughter) It came to the table a bright, almost shimmering, white color. The chef had overcooked it. Like twice over. Amazingly, it was still delicious. Who can make a fish taste good after it's been overcooked? I can't, but this guy can. Let's call him Miguel — actually his name is Miguel. (Laughter) And no, he didn't cook the fish, and he's not a chef, at least in the way that you and I understand it. He's a biologist at Veta La Palma. It's a fish farm in the southwestern corner of Spain. It's at the tip of the Guadalquivir river. Until the 1980s, the farm was in the hands of the Argentinians. They raised beef cattle on what was essentially wetlands. They did it by draining the land. They built this intricate series of canals, and they pushed water off the land and out into the river. Well, they couldn't make it work, not economically. And ecologically, it was a disaster. It killed like 90 percent of the birds, which, for this place, is a lot of birds. And so in 1982, a Spanish company with an environmental conscience purchased the land.

What did they do? They reversed the flow of water. They literally flipped the switch. Instead of pushing water out, they used the channels to pull water back in. They flooded the canals. They created a 27,000-acre fish farm — bass, mullet, shrimp, eel — and in the process, Miguel and this company completely reversed the ecological destruction. The farm's incredible. I mean, you've never seen anything like this. You stare out at a horizon that is a million miles away, and all you see are flooded canals and this thick, rich marshland. I was there not long ago with Miguel. He's an amazing guy, like three parts Charles Darwin and one part Crocodile Dundee. (Laughter) Okay? There we are slogging through the wetlands, and I'm panting and sweating, got mud up to my knees, and Miguel's calmly conducting a biology lecture. Here, he's pointing out a rare Black-shouldered Kite.

Now, he's mentioning the mineral needs of phytoplankton. And here, here he sees a grouping pattern that reminds him of the Tanzanian Giraffe. It turns out, Miguel spent the better part of his career in the Mikumi National Park in Africa. I asked him how he became such an expert on fish. He said, "Fish? I didn't know anything about fish. I'm an expert in relationships." And then he's off, launching into more talk about rare birds and algaes and strange aquatic plants. And don't get me wrong, that was really fascinating, you know, the biotic community unplugged, kind of thing. It's great, but I was in love. And my head was swooning over that overcooked piece of delicious fish I had the night before. So I interrupted him. I said, "Miguel, what makes your fish taste so good?" He pointed at the algae.

"I know, dude, the algae, the phytoplankton, the relationships: It's amazing. But what are your fish eating? What's the feed conversion ratio?" Well, he goes on to tell me it's such a rich system that the fish are eating what they'd be eating in the wild. The plant biomass, the phytoplankton, the zooplankton, it's what feeds the fish. The system is so healthy, it's totally self-renewing. There is no feed. Ever heard of a farm that doesn't feed its animals? Later that day, I was driving around this property with Miguel, and I asked him, I said, "For a place that seems so natural, unlike like any farm I'd ever been at, how do you measure success?" At that moment, it was as if a film director called for a set change. And we rounded the corner and saw the most amazing sight: thousands and thousands of pink flamingos, a literal pink carpet for as far as you could see. "That's success," he said. "Look at their bellies, pink.

They're feasting." Feasting? I was totally confused. I said, "Miguel, aren't they feasting on your fish?" (Laughter) "Yes," he said. (Laughter) "We lose 20 percent of our fish and fish eggs to birds. Well, last year, this property had 600,000 birds on it, more than 250 different species. It's become, today, the largest and one of the most important private bird sanctuaries in all of Europe." I said, "Miguel, isn't a thriving bird population like the last thing you want on a fish farm?" (Laughter) He shook his head, no. He said, "We farm extensively, not intensively. This is an ecological network. The flamingos eat the shrimp. The shrimp eat the phytoplankton. So the pinker the belly, the better the system." Okay, so let's review: a farm that doesn't feed its animals, and a farm that measures its success on the health of its predators. A fish farm, but also a bird sanctuary. Oh, and by the way, those flamingos, they shouldn't even be there in the first place.

They brood in a town 150 miles away, where the soil conditions are better for building nests. Every morning, they fly 150 miles into the farm. And every evening, they fly 150 miles back. (Laughter) They do that because they're able to follow the broken white line of highway A92. (Laughter) No kidding. I was imagining a "March of the Penguins" thing, so I looked at Miguel. I said, "Miguel, do they fly 150 miles to the farm, and then do they fly 150 miles back at night? Do they do that for the children?" He looked at me like I had just quoted a Whitney Houston song. (Laughter) He said, "No; they do it because the food's better." (Laughter) I didn't mention the skin of my beloved fish, which was delicious — and I don't like fish skin; I don't like it seared, I don't like it crispy. It's that acrid, tar-like flavor.

I almost never cook with it. Yet, when I tasted it at that restaurant in southern Spain, it tasted not at all like fish skin. It tasted sweet and clean, like you were taking a bite of the ocean. I mentioned that to Miguel, and he nodded. He said, "The skin acts like a sponge. It's the last defense before anything enters the body. It evolved to soak up impurities." And then he added, "But our water has no impurities." OK. A farm that doesn't feed its fish, a farm that measures its success by the success of its predators. And then I realized when he says, "A farm that has no impurities," he made a big understatement, because the water that flows through that farm comes in from the Guadalquivir River. It's a river that carries with it all the things that rivers tend to carry these days: chemical contaminants, pesticide runoff.

And when it works its way through the system and leaves, the water is cleaner than when it entered. The system is so healthy, it purifies the water. So, not just a farm that doesn't feed its animals, not just a farm that measures its success by the health of its predators, but a farm that's literally a water purification plant — and not just for those fish, but for you and me as well. Because when that water leaves, it dumps out into the Atlantic. A drop in the ocean, I know, but I'll take it, and so should you, because this love story, however romantic, is also instructive. You might say it's a recipe for the future of good food, whether we're talking about bass or beef cattle. What we need now is a radically new conception of agriculture, one in which the food actually tastes good. (Laughter) (Applause) But for a lot people, that's a bit too radical. We're not realists, us foodies; we're lovers. We love farmers' markets, we love small family farms, we talk about local food, we eat organic.

And when you suggest these are the things that will ensure the future of good food, someone, somewhere stands up and says, "Hey guy, I love pink flamingos, but how are you going to feed the world?" How are you going to feed the world? Can I be honest? I don't love that question. No, not because we already produce enough calories to more than feed the world. One billion people will go hungry today. One billion — that's more than ever before — because of gross inequalities in distribution, not tonnage. Now, I don't love this question because it's determined the logic of our food system for the last 50 years. Feed grain to herbivores, pesticides to monocultures, chemicals to soil, chicken to fish, and all along agribusiness has simply asked, "If we're feeding more people more cheaply, how terrible could that be?" That's been the motivation, it's been the justification: it's been the business plan of American agriculture.

We should call it what it is: a business in liquidation, a business that's quickly eroding ecological capital that makes that very production possible. That's not a business, and it isn't agriculture. Our breadbasket is threatened today, not because of diminishing supply, but because of diminishing resources. Not by the latest combine and tractor invention, but by fertile land; not by pumps, but by fresh water; not by chainsaws, but by forests; and not by fishing boats and nets, but by fish in the sea. Want to feed the world? Let's start by asking: How are we going to feed ourselves? Or better: How can we create conditions that enable every community to feed itself? (Applause) To do that, don't look at the agribusiness model for the future. It's really old, and it's tired. It's high on capital, chemistry and machines, and it's never produced anything really good to eat. Instead, let's look to the ecological model.

That's the one that relies on two billion years of on-the-job experience. Look to Miguel, farmers like Miguel. Farms that aren't worlds unto themselves; farms that restore instead of deplete; farms that farm extensively instead of just intensively; farmers that are not just producers, but experts in relationships. Because they're the ones that are experts in flavor, too. And if I'm going to be really honest, they're a better chef than I'll ever be. You know, I'm okay with that, because if that's the future of good food, it's going to be delicious. Thank you. (Applause).

Ocean Temperatures – Changing Planet

The world’s oceans cover more than 70 percent of Earth’s surface. Millions of creatures, great and small, call the oceans home. These massive bodies of water play a crucial role in maintaining the planet’s delicate environmental balance, from supporting a complex food chain, to affecting global weather patterns. But rising air temperatures are warming the oceans and bringing dramatic impacts felt around the globe. Dr. TONY KNAP (Bermuda Institute of Ocean Sciences): One of the things warming does in, say areas off the United States, it creates a much bigger pool of warm water in the surface of the ocean that lends a huge amount of energy to hurricanes and tropical cyclones. THOMPSON: Dr. Tony Knap is the director of the Bermuda Institute of Ocean Sciences, or BIOS. Famous for its luxurious golf courses and pink sand beaches, Bermuda is also home to one of the world’s leading institutes for ocean studies, with a focus on water temperatures.

KNAP: Here off Bermuda, we have probably a better view of it then many other people are going to have over time. THOMPSON: Bermuda is located over 600 miles, or almost 1,000 kilometers, from the coast of North Carolina, in an area of the Atlantic Ocean called the Sargasso Sea. KNAP: We like to think of the Sargasso Sea in the North Atlantic as the canary in the coalmine. It’s the smallest ocean, it’s between North America and Europe and we think if we are going to see changes, we will see them first here in the ocean off Bermuda. THOMPSON: Scientists at BIOS have been measuring the temperature of the ocean since 1954, making it one of the world’s longest ongoing studies of ocean data. KNAP: Well you measure the temperature of the ocean in many ways. In the old days you used to do it with buckets and thermometers. Now you use sophisticated instruments called conductivity, temperature and depth recorders. THOMPSON: These recorders, called CTDs, are large measuring instruments lowered deep into the water at specific locations in the ocean. On this day, Knap and his team are headed to “Station S.

” QUENTIN LEWIS, Jr. (Captain, R/V Atlantic Explorer): The weather is not going to be our friend today, unfortunately. The winds out of the west, it’s 35-40 and some higher gusts. The seas are anywhere from 14 to 16 feet or higher. THOMPSON: Lowered to a depth of three kilometers, or just under two miles, the CTD records temperature, salinity, carbon dioxide levels, and captures water samples. KNAP: This is a screen for the output on the CTD. The temperature will be in red, blue is salinity or the saltiness, and yellow is the oxygen content. THOMPSON: At BIOS, all of the data is then carefully logged and analyzed. Dr. NICK BATES (Bermuda Institute of Ocean Sciences): With this instrument we can see changes that happen over the season, over the year. And then from year to year.

THOMPSON: Using ocean temperature data going back several decades, BIOS research can trace the warming trend. In the past 56 years, it has risen half a degree Celsius. KNAP: Since 1954 we’ve seen, on average, the temperature increasing by a small amount, an equivalent to what is really a half a watt per year which is, doesn’t seem like a lot but over the whole of the ocean, it’s a lot. THOMPSON: What’s a half a watt? KNAP: It’s not much. It’s about a 100th of a degree per year. It’s not a lot. THOMPSON: But that small a difference can make, have a huge impact? KNAP: Yeah. THOMPSON: Really? KNAP: Yeah, because it’s going on every year. You think about how big the ocean is, and how deep it is, and how much energy it has, I mean it’s a tremendous source of heat. THOMPSON: So where is that warming coming from? KNAP: The warming we believe is to due to changes in CO2 in the atmosphere, the atmosphere getting warmer and the surface of the ocean getting warmer.

And that transfer of heat is being made into the ocean. THOMPSON: So what is the impact of a warmer ocean? The rising temperature causes the ocean to expand, and raises sea levels. KNAP: The tides going up by 3.2 millimeters a year. Half of that is attributed to the ocean warming down to 700 meters. The oceans on average 4,000 meters deep so it has a lot more to expand. THOMPSON: Warming temperatures also impact the growth rates of certain organisms at the very bottom of the ocean food chain, like phytoplankton. And so if you see changes in phytoplankton, does that mean that we are going to see changes in the food chain at the ocean? KNAP: If the organisms that eat those organisms, OK, eat the plankton, for example, can’t eat those plankton, then yes you’ll see changes. THOMPSON: And the small changes being recorded could bring even stronger storms.

This report published in 2005 in Science Magazine shows the gradual rise of the number of Category 4 and 5 hurricanes over recent years. An increase in storm intensity like this many scientists believe is the result of the warming of the oceans. KNAP: You think about how big the ocean is, and how deep it is, and how much energy it has. Even if you look at difference in hurricanes intensity, etc., one, one and a half degree centigrade in the water column of one hundred meters makes a massive amount of difference. THOMPSON: Small changes with big consequences for the creatures in the sea and all the people who live along the coasts..