Hello All,
Thanks Cassandra for a reply. I don’t think there is any problem in science or communication here. Although I am sorry it is often challenging to write in email
format in a manner that is subtle. So apologies from me if that aspect caused some bother. I suppose I could have been less direct. I focussed only on the issues I see as suggested by your reasons for doing this study. I am entirely confident of my science
and communication on this issue. I have a 45 + years of interest in finches, in reproductive biology, avian social and sexual behaviour, etc. There is always more to learn. I am certainly on your side, which is why I took the time (and lost quite some sleep)
to respond to your first message. I also took a choice to respond to the list, rather than just to you, which could easily (maybe should have) been done the other way. But I think the issues about the birds are interesting and I thought it highly likely that
others would have responded with similar concerns as I have, and that I could add to the discussion with more detail.
One other little point. I don’t see the issue of mouth markings on finch chicks as in any way a complex evolutionary issue. To make one comparison, there are
a vast number of flowering plants, along many different lineages, that have evolved markings along their flowers, that appear to act as guides for all sorts of pollinators (mainly insects and birds), and several such cases have become highly specialised connections
between them. That a group of finches have similar markings in the mouths of their chicks for similar reasons, (thus a connection only between adult and chick of the same species, rather than hugely different organisms), is not that notable by comparison.
Similarly, the mimicry achieved by one group of parasitic finches is somewhat routine, in the scheme of things, of the range of strategies that parasites have.
I think it is obvious that I was not writing primarily to ask questions. When I typed “Has
the ANU’s ethics committee
considered this?” About my concern of the likelihood of predation from Currawongs markedly altering the results of the study by eliminating your study materials,
I admit that was based on a presumption that the answer to this question was no. As such this is an awkward assumption because I have no knowledge either way.
Now to the point of my earlier message. I have seen so many bird research projects over the years and had a variety of roles in many of them. I have heard many
presentations at COG and other forums over the past 40 + years. I see many in which I have thought, wouldn’t it be better if the rationale for this study was better worked out from the start, to be realistic and achievable. When I did my thesis, I certainly
wish I had a better plan as to how to answer the questions I had, than I in fact did. I would have made far fewer mistakes and had a far better outcome. Sadly I did not get much advice. I think the aspect of the mouth markings of finches is moderately interesting
and the mimicry taken up by a group of parasitic finches in Africa is also interesting. The idea of research into the markings inside nestling estrildid finch mouths at Jerrabomberra Wetlands is fine.
My reasons for responding to you in the way I did are
all to do with ethics. Much more than the science involved. I am concerned that you are setting out to devote three years of your life in a once in a lifetime opportunity and in three years you might be doing a talk to COG or whoever, making a case for
an investigation that tries to link things, where there is no link. Sure I might be proved wrong after three years and that is fine. My ethics compels me to express an opinion and some advice to you at the start of your study, rather than regret not having
the chance to do so, at the end. Sure it is your choice to consider it or not. I suggest get more advice from others on the suggestions I made and your project proposal. I am really concerned at the idea that “Did we have a parasite and it has gone
extinct?”
If you wish to consider this by looking at local finches, it is so outlandish an idea that it really needs to be called out at the start.
Philip
From: Cassandra Taylor [
Sent: Wednesday, 10 October, 2018 4:19 PM
To: Philip Veerman; 'Canberrabirds'
Subject: RE: Research into the markings inside nestling estrildid finch mouths at Jerrabomberra Wetlands
Hello to Philip and the COG chatline,
In my initial e-mail, I invited people to ask questions as I strongly believe that it is vital to foster an open and honest communication channel between
the science community and the general public. Both sides have much to learn from the other. Scientists, in general, are poor communicators of our work. Many of us are working hard to improve, and certainly earnest efforts have been made to reach out and explain
our work in recent years.
In an effort to be transparent I put more information in my initial e-mail than I needed to. I gave context for my research, and for my reason for approaching
nests. By being honest and transparent I communicated my enormous respect for the COG community.
Due to the nature of the way the questions were asked, in addition to the method in which they were delivered, I am not going to address them. I do not believe
they were asked in a genuine effort to understand or to learn. I hope this does not discourage other enthusiastic bird lovers from contacting me.
Thank you,
Cassandra
From: Philip Veerman <>
Sent: Wednesday, 10 October 2018 8:51 AM
To: 'Canberrabirds' <>; Cassandra Taylor <>
Subject: Research into the markings inside nestling estrildid finch mouths at Jerrabomberra Wetlands
Hi Cassandra,
I am sorry to say I have an additional concern about this study. It relates to “This research
has been submitted to ANUs ethics committee and has been granted approval to proceed. No birds will be harmed as part of this research. So if you see me looking in nests, feel free to come up and say hi, I will have copies of all my licences and permits for
this research.”
Finches have a 2 week incubation and 3 week nestling period. This is long by small bird standards. They do not have much to offer by way of nest defence from
predators, apart from having a domed nest and building it in dense cover. The Diamond Firetail has a habit of building a nest in the base of an eagle’s nest, thereby getting protection from currawongs etc. The species you are likely looking for, the Red-browed
Finch nests in dense and preferably prickly vegetation. My concern is that you are concerned about being seen by us whilst examining nests. I am not concerned about us. I am concerned about nest predation and the validity of your project. There are many Pied
Currawongs there. They watch people. They will most likely be watching you whilst you are at the nests. If the foliage is sufficiently accessible for something as big as a person to get to the nest (through the prickles) and do whatever for even a few minutes,
then I suggest that the cover the finches rely on for protection from currawongs has been breached. I suspect not a lot of nests will survive this. I hope I am wrong but I suspect most birds will be harmed by this (not by you) but by exposure to predation.
This would surely also compromise your results. These are obvious concerns and I am surprised I did not think of this yesterday. Has the
ANU’s ethics committee
considered this? (Apart from my other concerns.) If not, why not? As I say I hope I am wrong.
Philip
Hi Cassandra,
Thanks for raising this interesting question. I for one am very perplexed at this research idea and it would be interesting to hear an explanation.
I make some points:
The mouth markings of our finches are well known. Immelmann’s 1965
Australian Finches book described it and had a diagram of the pattern for 14 of them. All these finches build covered nests, so it is potentially dark inside the nest, so bright mouth marking in the chicks can act as a feeding guide in a dark nest, for
the parents and help them get fed. Our finches crouch and hold their heads low and twisted upwards, unlike the chicks of most birds, that beg in a very forward pose. So maybe the mouth marking help in that situation. That the Gouldian Finch also likes to nest
in a tree hollow is only a slight change. Given that it is an established feature of the group and well shown in Australia and Asia, it is really hard (extremely hard) to understand how it could be suggested in any way due to a very particular situation of
parasitism from a small group of birds that only occurs in Africa. I certainly have never heard that idea. Surely the mouth markings arose early in the evolution of the Estrildids. As that group is big and widespread with a lot of variation, surely this predates
in history a long way before the relatively recent parasitic Whydahs came into existence. There is nothing odd about brightly coloured mouths of many bird chicks, this is simply an extra elaboration. I am entirely comfortable with the simple and straightforward
idea that the range of patterns that now occurs is simply a result of radiation that has occurred since then. I don’t see it as any more mysterious than that the plumage patterns of adults of all species are now different, although showing some variations
on themes. Just random variations on an established somewhat unimportant feature. I would expect that there is benefit in having these mouth markings but little relevance in variations. There can be selective pressure to keep species separate, because they
all have similar nesting habits and many species nest near other species (in places where several species are common). I expect there can be selection benefit in a feature that ensures that birds don’t accidentally go to the nest of another species and adopt
the wrong chicks. This could lead to wrong imprinting, to which finches are susceptible. Thus the mouth markings can guide the feeding by parents and maintain species separation. Then again, our finches will readily hybridise in captivity, presumably hybrid
chicks show a mix on this feature and both parents will still feed them, so that the selective pressure can’t be too strong.
As for the Whydahs that parasitise some African finch species, they are hardly cuckoos. They are another group of finches and as far as I am aware they don’t
directly harm their hosts. But I could be wrong on that (for example food competition). As in this Wikipedia extract below.
As for:
The leading theory for these mouth markings is that they evolved for parents as a way to discriminate against parasites in the nest. Over time, the mouth markings have co-evolved, leading to elaborate and intricate designs.
How can that be? Given that the mimic successfully copies these markings, they are hardly
aiding discrimination. There is no benefit in the finch for co-evolution. There is benefit for the parasite to evolve better copying but that is surely a one way process. There may be benefit for the model species to keep changing to make copying harder. Also
why should that be? We don’t have parasites here, so on the evidence of all of Australia, that whole suggestion just falls in a heap.
As for
Did we have a parasite and it has gone extinct?
Well surely that is a crazy idea. It asks for a huge leap of very weird logic. I suggest it requires that we had about 18 species of parasite that have all mysteriously become extinct whilst the finches did not. As each species has its own pattern.
I wonder what sort of questions are being asked and how it is possible to frame any kind of research
in any way that can give results that can elucidate anything of relevance to the special case of the few species of African nest parasites that happen to have caught onto the clever trick of locally evolving a very particular set of mimicry (calls and mouth
markings) to their very particular set of host species. The benefit to the parasite of copying, is immediately obvious and I can’t imagine anything even slightly mysterious about that. So what is the question?
I am a little perplexed at the field work in Canberra, as we only have one very common breeding native
finch here, plus two more that are surely less easy to find breeding. Most finches are in northern Australia. I am not even aware that we have any captive populations of the Whydah species in Australia. I believe they are not easy to maintain.
Philip
Hello,
My name is Cassandra Taylor, I am a PhD student at ANU, working on Estrildid Finches. Soon I will be undertaking work in the Jerrabomberra Wetlands, and Michael the Senior Ranger
at the wetlands asked me to post about it on COGs chatline. This is just to keep everyone in the loop with what is happening, and so that if people see me touching nests etc., they know what is happening and not to be alarmed.
I will explain a bit about my research below, to give you context for why I will be looking at nests and nestlings.
My research will be looking at the markings inside nestling estrildid finch mouths, see the photo below
Every Estrildid finch species in the world has unique mouth markings for that species. Estrildids occur in Australia, Africa, and Asia. Almost all Australian finches are Estrildids
(Zebra, Gouldian, Red-brow, The firetails, Double-bars).
In Africa the Estrildids are parasitised by Vidua finches (think Cuckoos), and the parasites have evolved identical mouth markings, see photo below
The parasite is on the left (A vidua finch), and the estrildid is on the right. They grow up to look completely different!
The leading theory for these mouth markings is that they evolved for parents as a way to discriminate against parasites in the nest. Over time, the mouth markings have co-evolved,
leading to elaborate and intricate designs.
However in Australia our finches exhibit these elaborate markings in the absence of parasitism.
This raises lots of questions! Did we have a parasite and it has gone extinct? Are they a vestigial trait that has carried through time due to a low maintenance cost? Or is the
theory in Africa not the complete story? If you have ever seen a Gouldian Finch chick, you would have noticed the glowing orbs on the flanges of the beak. Interestingly this is our only compulsory finch cavity nester, perhaps these orbs guide parents to chicks
mouths in dark nests?
Over the next 3 years, I hope to answer these questions! And discover what these elaborate mouth markings communicate to the parents.
This year I am engaging in some field work at a few sites around Canberra, and one of those is the Jerrabomberra wetlands. I will be photographing chicks mouths at several points
through their development in the nest.
This research has been submitted to ANUs ethics committee and has been granted approval to proceed. No birds will be harmed as part of this research.
So if you see me looking in nests, feel free to come up and say hi, I will have copies of all my licences and permits for this research.
If you have any questions feel free to contact me,
All the best,
Cassie
Cassandra Taylor
Ph.D. candidate, Langmore Lab
Division of Ecology & Evolution
Research School of Biology
ANU College of Science
RN Robertson Building
46 Sullivans Creek Road
The Australian National University
Acton ACT 2601 Australia
M +61 415 299 016
E
W
http://biology.anu.edu.au/research/labs/langmore-lab-avian-evolutionary-and-behavioural-ecology
