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  1. J

    What is a species?

    In Oriental Bird Club Taxonomic Summaries, they reference years of separation, which presumably are stated in the original paper arguing for species status. Do you know if author’s of Scientific papers can be ‘relied upon’ to use non-coding chromatin, without presumed function or selective...
  2. J

    What is a species?

    Can any examples using humans really be applied to nature in general? We are a unique species in that we have created a society where physiology is not important to survival. We also are rather non selective in pairing - yes we fill our fashion magazines with stereotypes of beauty, but mostly...
  3. J

    What is a species?

    Interesting that rates vary. Doesn’t this make the calculation of when a species diverged highly complex? I.e a calculation of what mutations have occurred in which parts of the chromosome and at what assumed rate? Presumably also some gene mutations are dominant? I can’t remember the ‘rules’...
  4. J

    What is a species?

    Yes this was my assumption. But the counter to this is that if mutations occur per x replications, the larger the populations the more chance of a mutation occurring. There is probably a complex model that balances chance of mutation verses likelihood of becoming influential. Speciation...
  5. J

    What is a species?

    My knowledge of genetics is pretty poor, and my assumptions on speciation based on ‘the blind watchmaker’, which is fairly dated. But how can the process be non-random? The process of gene replication (and bad copy) is surely non-selective. I can see how this forms a dividing point (isolation...
  6. J

    What is a species?

    Never considered this. I suppose that for a genetic ‘advantage’ to ripple out from the source throughout a widespread taxa could take thousands of years, whereas for limited island populations, an advantage would be incorporated across the whole population more quickly. But then again, if we...
  7. J

    What is a species?

    Now I am confused. According to good old Wikipedia ‘The Homo genus is evidenced by the appearance of H. habilis over 2 mya,while anatomically modern humans emerged in Africa approximately 300,000 years ago.’ So why is divergence of 10mya often quoted for bird species (which generally have a...
  8. J

    What is a species?

    I am relying on the expedition geologist who advised the NZ alps were 5 million years old (not the NZ landmass as part of Gondwana). Unfortunately I cannot find anything on the net to confirm the age. Interestingly, the geologist advised the last min ice age in NZ was only 16k years ago, when...
  9. J

    What is a species?

    Interestingly I was recently on the Antipodes (well doing a zodiac cruise around), where there are two endemic parakeets. According to the expedition geologist, the islands are only 200,000 years old. This suggests to me that either speciation occurs much quicker than we think, or that in this...
  10. J

    What is a species?

    This would be very complicated. Unless we went around testing every bird, it would need to be an individual judgement - so we would then be into that mode of 'that Jon Bryant cheats and always over-estimates - that hybrid gull he saw the other day was 10% max and he is claiming it as 50%!' Not...
  11. J

    What is a species?

    I have a tendency to make loads of typos, which I then try to edit - if is was a fibber, I would blame it on auto correct, but in reality it is just typing to fast and not thinking!
  12. J

    What is a species?

    I recall this was a ‘putative’ Atlas Fly, reported at Flamborough Head, not a definite claim, although it did attract some interest from twitchers for ‘insurance purposes’. A possible Med Fly likewise also attracted some interest, but was a much shorter stayer, so not so many twitchers finally...
  13. J

    What is a species?

    I suppose this goes back to my original comment as to whether a species is a human construct, necessary for classification and cataloging. If so, and we are not able to consistently place taxa in the right box, then it could be argued that the system has gone too far and is too granular. But...
  14. J

    What is a species?

    My understanding is that moult cycles in gulls are rather protracted and some feathers are shed almost year round - so feathers could also be collected at the wintering grounds. Also I think DNA can be obtained from poop, so another easy thing to collect in winter. I think a putative American...
  15. J

    What is a species?

    Caspian Gull was only recently detected as visiting the U.K, with the first records in the 1990s. I am not suggesting that it was discovered due to voice, but it does have a distinctive voice and ‘albatross’ display. The Latin name (including the original subspecies name) is cachinans, meaning...
  16. J

    What is a species?

    I have not visited the Great Lakes in winter, so am not aware of the situation there. However, I don't really think that the situation in winter is really as straightforward as attributing the spread of birds to an east west cline. To quote Birds of the World. glaucoides - some Greenland...
  17. J

    What is a species?

    This makes things even more complex and perhaps a little bias. As an example, we know that large Gull hybridise quite often. We have recorded that Marsh and Blyth’s Reed Warbler hybridise, but I think the warbler hybridisation has only been recorded through the encounter of mixed pairs. I think...
  18. J

    What is a species?

    I was thinking about clines the other day. Does it really show that a subspecies is dubious, or might it just be a current snapshot of the slow advance of an advantageous form, with a wide band of hybridisation. Some east-west clines do not seem to be able to be readily mapped against a...
  19. J

    What is a species?

    The DB article stated that pair bonds are actually formed in late winter prior to spring migration, so mixed pairing can be reasonably determined in early spring, in the wintering grounds. The article also stated that typical types have different vocals, which again could be established on the...
  20. J

    What is a species?

    I think this is the extreme end of PSC. As I stated earlier in the thread Birdlife suggested that a PSC list could have circa 16k species - there are circa 11k species and 19k subspecies, so 16k is well off considering all subspecies as species. The Dutch authority only looks at the Western...
  21. J

    What is a species?

    Really? I am only thinking of supporting information, but if we look at Thayer’s Gull as an example Do we witness pair bonds being formed on the wintering grounds, as has been suggested? If so, what percentage of pair bonds observed during late winter/spring involve birds of mixed characters...
  22. J

    What is a species?

    A suggestion I made to Cornell, was whether through a University website, the University could engage citizen science to collate missing information for species assessments. Many of us travel a lot more and have appropriate equipment (high res cameras, sound recording equipment etc.), so could...
  23. J

    What is a species?

    H&M were apparently invited, but didn't participate as they wanted to protect their intellectual property. A bit odd, as (perhaps a bit rudely) I suggest that the their intellectual property is not maintaining its value and is probably falling sharply! - No updates since version 4 in 2016, and...
  24. J

    What is a species?

    I have been trying to create a diary and listing programme for some time - I know there are tools out their, but I like BirdLife's taxonomy (missing from other packages, don't like Birdtrack's (IOC) non-existent filters for foreign birding, and rather like most UK birders, I like EBird's easy of...
  25. J

    What is a species?

    Very interesting, I am learning! I can imagine that this is even harder to try and determine, especially for birds that rarely hybridize (as they generally not attractive to each other, or are isolated). I can't imagine our knowledge of genes will every be able to answer will a hybrid be less...
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