The Disappearing Monarch and the Oldest Mammal on Earth

1990s pretty awesome right we had Game Boys and Pokemon and Boris Yeltsin and a whopping 1 billion monarch butterflies living on earth unfortunately a lot of Jane since then they still have faux c'mon but Boris Yeltsin was replaced by Vladimir Putin who's not nearly as much fun and the number of monarch butterfly's has dropped by a whopping 90 percent there are now only 35 million of the butterflies left the last week the US Fish and Wildlife Service said it was going to consider including the monarch butterfly on the endangered species list for the first time ever scientists think the butterflies are disappearing at least in part because of a diminishing supply of milkweed the plants that are the sole source of food for monarch caterpillars every year monarchs embark on an epic 4800 kilometer migration between Canada and Mexico along the way they stop in the Upper Mississippi River Basin also known as the Midwest and lay eggs underneath milkweed leaves which until recently were all over the place then the larvae hatch and feed on the plants on the Midwest is the agricultural heartland of the United States if you live here and you eat food you eat food from there so milkweed often grows in corn and soybean fields but over the past 20 years more farmers have been using herbicides with the active ingredient clive phosphate glyphosate kills plants by blocking their enzyme pathways farmers can plant genetically modified crops that are resistant to glyphosate meaning they can spray just sort of indiscriminately and their crops won't die but milkweed that will die as a result the Xerces Society for invertebrate conservation estimates that monarchs have lost more than 660,000 square kilometers of milkweed habitat in the Midwest due to the use of glyphosate that's an area larger than France scientists suspect the climate change in deforestation in Mexico may also be contributing to the Monarchs disappearance so over the next year the US Fish and Wildlife Service will review the proposal to lift the iconic butterfly as an endangered species if it gets listed that could be an extensive habitat protection on both public and private lands in the United States but even then it'd be a long time before monarchs got back to where they were in the 90s now if you ask a bowhead whale would it mist about the good old days it would have to think back a lot further than the 1990s more like the 18 so heads can live for more than 200 years the oldest of them ever found was 211 making them the world's longest living mammal at least that we know of they have a thousand times more cells than a human but they don't seem to suffer from the same rates of cancer or age-related diseases that we do so in a study published this week researchers sequence the entire genome of the bowhead in order to figure out how these whales can live for so long a sequence genome is kind of like a road atlas establishing the locations and kinds of genes within an organism's chromosomes by sequencing the genome of the bowhead and comparing it with other mammals including humans cows mice and their closest relatives the Minka whale scientists discovered that many of the differences in bowheads genes were associated with aging for instance they noticed a mutation in the gene that affects what's called the proliferating cell nuclear antigen or PCNA which helps repair damage to DNA strands every time one of your cells divides into there's an opportunity for a little bit of that DNA to be damaged think of it like photocopying a photocopy over and over again eventually you're going to get some degradation too much DNA damage and the cell dies this is all part of the aging process so PCNA acts like a leash holding on to little bits of DNA that might break off during cell replication and the longer the bowhead cells stay alive the longer they stay alive which may explain why they can enjoy centuries and swimming around in the Arctic and eating zooplankton and doing whatever else they do for fun the scientists stress that they've only identified the differences between bowhead genes and those of other mammals law research needs to be done to figure out the secret to their record-setting longevity so we're one step closer to understanding why some of these whales are older than me and my grandma and my great grandma and the whole state that I live in thanks for joining me for this first scishow news of 2015 if you want to help us share science with the world you can become a supporting subscriber at subbable.com/scishow and don't you forget to go to youtube.com/scishow and subscribe you you

Channel: SciShow

Views: 363,230

Keywords: biology, longevity, bowhead whales, whole genome sequencing, animals, butterflies, monarch, milkweed, glyphosate, herbicides, gmos, genetically modified organisms, agriculture, crops, plants, u.s. fish and wildlife service, endangered species, list, act, science, hank green, sci show

Id: oOjYT9EqH5E

Length: 4min 13sec (253 seconds)

Published: Fri Jan 09 2015