(Intro)

Michael: Scientists are discovering and describing new species all the time, and there are probably millions of creatures on Earth still waiting to be found.  There's no doubt that some of them are lurking in the bottom of the ocean or deep in jungles, but a lot of them might be closer to home, in our cities.  Better DNA analysis techniques and new attention to urban habitats are revealing more biodiversity from Los Angeles backyards to the feet of the Statue of Liberty.  These new species are usually small or look a lot like other animals, so they tend to go unnoticed in some of the busiest places in the world.  Here are seven of them.

1) If you are looking for a new species in Brazil, you might think to start in the Amazon Rainforest, not in Sao Paolo, the most populous city in the Southern Hemisphere, but that's exactly where a 2014 biological survey of mollusks turned up a never before seen land snail in the woods of the city's (?~0:56) park.  It's a little bigger than other species in its genus.  It can have light beige shells instead of pure white, but snails are also identified by whorls on their shells, those characteristic spirals which are consistently throughout their species.  So it was the little details that set the Sao Paolo snail apart.  The tiny protoshells of newly hatched babies had one and a half whorls instead of two, unlike other members of the snail genus.  Plus, there are 16 little ridges called threads on the top-most whorl in adults instead of over 20.  Researchers picked its scientific name, Adelopoma paulistanum based on the word 'paulistano', or someone born in the city of Sao Paolo, and they speculate that the park is just a fragment of native rainforest, where the tiny snail was able to survive even as its habitat was mostly replaced with cityscape.

2) On the other side of the Southern Hemisphere in 2015, a pair of naturalists stumbled across three new millipede species in a city park in (?~1:48), Tasmania.  It can be tough to tell apart small arthropods, so one way is by examining the shape of their genitals.  The shapes differ between species so that individuals can only mate with their own kind.  When the discoverers brought these millipedes to an insect scientist or entymologist, one stood out because of the projections on the male's genitalia that apparently looked like the head of a jackal, so they named it Tasmaniosoma anubis after the ancient Egyptian jackal god.  

T. Anubis is common in the 12 square kilometers in the city's parks and nature reserves but it's missing from the eucalyptus woodlands right outside town.  The entymologist speculates that this millipede could have been widespread before the forests were damaged by sheep grazing and cleared for development.  Like the Sao Paolo snail, this jackal junked millipede seems to have found refuge in a patch of nature surrounded by city.  

3) In 2011, entymologists published the results of a survey of the bees of New York City and its suburbs with descriptions of many species, including a brand new species of (?~2:40) bee, collected in 2009 in the Brooklyn Botanic Garden, but here's the thing: all the bees aren't really new.  They could have been there before New York City was even New Amsterdam and stuck around after the city was built.  Chances are, scientists had even stumbled across some of these species without actually knowing they were different insects.  (?~2:57) bees are about the size of a grain of rice and so similar that you usually need genetic information to tell them apart, and a new technology called DNA Barcoding does just that.  This technique uses short DNA sequences that are part of the mitochondrial genome and gets passed down by females and usually differs between species, so with a tiny tissue sample and an evergrowing native base of barcode sequences, scientists can quickly identify lots of specimens.  The Botanic Garden bee, named Lasioglossum gotham after its city home, was actually one of four New York species that the survey turned up.  El gotham hasn't made an appearance in a Batman movie yet, but if the Caped Crusader ever needs a tiny insect sidekick, he knows who to call.

4) New York City has been harboring some bigger animals, too.  Scientists who study reptiles and amphibians, called herpetologists, had suspected that something was odd about some of the Big Apple's leopard frogs for a while.  In 1937, an ecologist named Carl Kauffeld noticed that some of the leopard frogs sounded like they had shorter and chirpier calls than the two known species.  He suggested in a paper that maybe there was a third, undescribed species lurking in the city's ponds, but the idea didn't have enough evidence to catch on.  

At least until 2014, when a team of scientists thoroughly studied some of the squeaky sounding frogs and published a paper.  They first caught these leopard frogs on Staten Island in 2008, only ten miles from the feet of the Statue of Liberty, and realized they were something unique.  Though they were discovered in New York City, call recordings suggest this species can be found from Connecticut to North Carolina.  Upon closer inspection, these amphibians had minor physical differences from other leopard frogs.  Their vocal sacs were a bit bigger and their leg colors were a bit darker, but the defining evidence was genetic.  The herpetologists sequenced several sections of thier mitochondrial DNA and some nuclear genes so they confirmed that this leopard frog was a unique species and dubbed it Rana Kauffeldi after the man who first proposed that it existed.  

5) Like the New York scientists puzzling over frogs, biologists thought there might be something weird about the bottlenose dolphins near Melbourne, Australia.  Over the years, they were lumped in with species in the genus (?~4:53).  Scientists chalked up any physical  variations to differences between males and females, from skull shape and the stub of your nose to a unique color pattern.  In 2011 though, marine biologists settled the matter once and for all with some genetic analysis.  They examined the dolphins' mitochondrial DNA plus repeating sequences of nuclear DNA called microsatellites.  Many microsatellites don't usually code for proteins, so they mutate more often than other parts of the genome, making them useful in identifying different species.  

So these tests reveal that the one hundred or so dolphins living beneath Melbourne skyscrapers were an entirely different species.  The scientists named them Tursiops australis or the Burrunan Dolphin after an Aboriginal phrase that basically means 'porpoise'.  The only other known population is even smaller, around 50 dolphins that live in a network of coastal saltwater lakes about 100 miles away.  Since there are so few of them, they're really vulnerable to human threats like our pollution, so the biologists that identified them are advocating for their protection under Australia's endangered species laws.  

6) Now, if discovering and describing one new species sounds impressive, imagine finding 30.  I'm talking about flies.  See, the Natural History Museum of Los Angeles started a project called BioScan in 2013 where entymologists worked with Los Angeles homeowners to put insect trapping tents in their backyards for science.

The researchers at the museum have been collecting and studying all these insects to learn more about the biodiversity of the area, and as of 2015, they found and described 30 previously unknown fly species, all from a family called the phorid flies, these humpbacked insects about the same size as fruit flies.  Just like with millipedes, fly species' genitals can be really distinct, even when the rest of their bodies look pretty much the same.  So the researchers identified most of these new species using careful examination with microscopes, and all but one of them were named for the citizen scientists that hosted the insect trapping tents where they were found.  Even though we tend to think flies are annoying, they play important roles in the ecosystem, preying on insects pests and eating organic junk.  By monitoring their populations, plus those of other insects, scientists can learn more about how this urban ecosystem is changing over time.  

7) Most of these species that we've talked about were probably there before us humans and our huge buildings, but can urbanization cause new species to evolve?  Take the so-called coywolf, a hybrid animal that's part coyote, wolf, and domestic dog.  Coywolves aren't a recognized species right now, because really, they're just eastern coyotes with some other DNA mixed in, but some people believe they could be headed that way.  Coyotes are native to western North America and have been gradually expanding eastward since the 1800s as native predators disappeared and forests were cleared.  There, they started the encounter the remnants of eastern wolf populations, and even domestic dogs, and occasionally, these animals interbred.  Unlike sterile mules produced by horse and donkey mating pairs, these species are biologically similar enough that the hybrid eastern coyotes are fertile.  In the last decades, scientists have started to analyze eastern coyote DNA, especially using variations called single nucleotide polymorphisms, or SNPs, which can reveal genetic links between different animals.  A paper published in 2013, for example, studied around 430 of these critters and found that they shared 30% of their DNA with wolves and 10% with dogs.  Behaviorally, they're also a hybrid and seem to be more suited to urban environments than western coyotes or wolves.  Unlike scrappy solitary coyotes, they hunt in small teams, but they're smaller than wolves and don't mind living near people, meaning they can survive in lots of habitats.

So are these eastern coyotes really the beginning of a new species?  For now, they're not, but if these animals become more genetically distinct over time, then biologists might give them the new species stamp of approval, and coywolves will be more than just a nickname for these hybrids.

Around the world, habitat loss is a major threat to wildlife.  Just because some animals can live in densely populated urban areas doesn't mean it's actually the best thing for them.  Still, these seven species show that we're just beginning to appreciate the biodiversity in cities.  Who knows, there could even be some new species hiding in your own backyard.  

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