new species

[crudshoveller]

I have asked this question several times elsewhere and never got anything but an evasive and unsatisfactory answer:
Excluding microscopic and simple organisms, which is the most recently arisen new species of creature - or even ONE of the most recent. Approximately how long ago did it appear as a distinct and separate species. From one answer I received it almost seemed 'species' is a spurious and wholly indeterminate and untenable distinction invented by Charles Darwin for the convenience of his famous theory of evolution.
Thanks

[metroid0714]

It's very difficult on the internet to track down news of new species that appear, however, you may want to check out the following sites:

http://www.sciencedaily.com/releases/20 ... 143615.htm
- This page contains recent information (10/31/2006) on new species that were just discovered in Hawaii.

http://www.sciencedaily.com/news/plants ... w_species/
- Occasionally this page will post information on new species that have been found. I found the first page above on this site.

I hope this helps you and good luck.
JJ

[MelissaB]

Crud,

Interesting question! Many scientists now consider the apple maggot, Rhagoletis pomonella, to be a separate species from the hawthorne fly. At the moment, though, from what I could find the two still have the same scientific name. There's more information here: http://en.wikipedia.org/wiki/Apple_maggot. Because apples were introduced to North America between 1800 and 1850, we can reasonably assume the speciation has taken place within the past 200 years or so.

Other recent speciation events include the domestic dog, Canis familiaris, from the wolf Canis lupus, the domestic cat, and the domestic chicken Gallus gallus. I'm not sure of the exact dates for these species, but I believe they're believed to have separated from their wild counterparts within the past 10,000 years and no later than 15,000 years ago.

Many different species of bird are believed to have speciated during the last glaciation when North America was mostly covered in ice.

The confusion you may have run into involve some very heated debates over exactly what should define a species. Before the 1940s, it was generally assumed that groups of animals that looked different were different species--sometimes causing males and females of the same species to be considered separate species because scientists didn't know any better!

The definition most people use today was put forth by Ernst Mayr in the 1940s. It says that species are groups of organisms which do not interbreed or, if they do, do not produce fertile offspring. Most people would tack on 'in the wild' to that since you can have functional hybrids of some animals that most people consider to be separate species--like lions and tigers, oh my!--in zoos where the animals actually interact with each other.

There are also genetic definitions of species, which can be complicated but generally state that species are groups of organisms on separate evolutionary trajectories. This means there can be interbreeding, but if there's no significant amount of gene flow between two groups of animals they're separate species. Using this definition of a species often means that there are way more species than are currently recognized--so, for example, some species concepts would multiply the number of species of birds by a factor of 10! Obviously, this is a very politically charged issue in the United States given the Endangered Species Act, and so there's a great deal of debate over it that's more political than scientific.

[crudshoveller]

Metroid - thanks for your help with this problem.
Melissa - thanks for your helpful and very comprehensive response.