Fig.1) Left: Anolis bimaculatus male (top) and A. leachii male (below) for comparison. Right: adult male A. leachii x A. bimaculatus hybrid.
We all know examples of interspecific hybrids in animals such as the Liger, the Zhorse or the Calico Chuckwalla or even intergeneric hybrids in plants such as orchids. Even within Anolis, there are well known examples of interspecific hybrids such as Anolis aenus x Anolis trinitatis on Trinidad.
I was able to produce fertile hybrids of different members of the bimaculatus group in my breeding facility which I want to show you in this post.
I am a private reptile keeper and breeder and have been working with Lesser Antillean Anolis, mainly in the sense of keeping and breeding, for 20 years. About three years ago, a good friend of mine told me his A. oculatus and A. terraealtae, which he kept together in a small greenhouse, had interbred and produced offspring. This was amazing to me, as I thought they were genetically too far apart. Shortly after that, out of interest and curiosity, I paired up some different species of my collection with the aim to produce hybrids. I was interested if it is possible to interbreed them in general, and also I wanted to see what the hybrids would look like. So in 2020, I paired up …
1) a male A. marmoratus marmoratus with a female A. ferreus
2) a male A. leachii with a female A. bimaculatus
In both cases, I used a large adult male and a young adult female that was raised single and had never been with any other Anolis before. I introduced the female into the male‘s enclosure and in both cases the male started courting the female immediately and mated with her. After the copulation, I separated the female again and collected the eggs over the course oft he next months. Long story short: I was able to obtain viable hybrids, raise some of them to maturity, paired this F1 generation again and produce viable F2 hybrids.
To describe the hybrids, I would say that they are generally very much intermediate in size and color regarding their parent species, both in males and females. But just look at some of the results (above and below):
Fig.2) Left: Anolis bimaculatus female (top) and A. leachii female (below) for comparison. Right: adult female A. leachii x A. bimaculatus hybrid.
Fig.3) Left: Anolis marmoratus marmoratus male (top) and A. ferreus male (below) for comparison. Right: adult male A. m. marmoratus x A. ferreus hybrid.
Now, I have some thoughts about this. We know that genomes diverge in isolation until the accumulated differences result in “speciation“ and/or reproductive isolation, as it is the case with the Anolis in the Lesser Antilles. With the use of molecular clocks such as the cytochrome b mitochondrial gene and geological dates, we can measure the genetic distance and estimate the timespan of separation of these taxa and project their phylogenetic relationships.
But how genetically distant or how long or over how many generations do two species have to be isolated to be genetically incompatible in the sense of not only being recognized as separate species by us, but also not being able to reproduce? Could Anolis be used as a model group for a question like that in general? Which would be the most distantly related Anolis species that would possibly be able to reproduce? Is there any specific pairing that would be of special interest?
Short disclaimer: None of the hybrids will return into nature. They live a healthy and fulfilled captive life like any other captive Anolis. They are just fine and healthy. Please do not blame me for this project.
Peter Uetz
This is fascinating because of the evolutionary implications but specifically for the molecular and genomic basis of “reproductive isolation” etc.
You should definitely get this stuff published and some parental and hybrid DNA collected and sequenced (or genotyped at least).
I don’t do this systematically, but I try to add data like this to the Reptile Database, where we currently have hybridization data for 22 species of Anoles. It may be interesting to map those to a phylogenetic tree and se who is hybridizing with whom …
Roger Thorpe
I addressed this in my 2018 paper “multilocus species phylogeny…..”. You can look at the estimated age of divergence of interbreeding species.
Gregor Weidlich
Hello Roger, thank you for your comment. Is this the link to the full text of your 2018 paper?:
https://www.sciencedirect.com/science/article/abs/pii/S1055790317308643
That is very interesting to read. Thank you for your work on the phylogeny of Lesser Antillean Anolis.
Roger
Yes, that’s the paper. There is a period of evolutionary time in which Lesser Antillean species can interbreed and it’s surprisingly long.
Antoinette Keen
I haven’t got a private breeding facility, nor am I a researcher like many of you. What I do have is training in professional herpatology, and a home in Central Florida. We have an outdoor lanai with many anoles who have taken up residence , searching for protection from storms, flooding, etc. I welcomed the critters, created a enviorment free from predators including fountains, & habitat re-creations . There are 3 breeding couples that moved in: a pair of brown anoles, a pair of green & a pair of morning geckos. I have read these ‘breeds’ do not get along, & will eat the young of their neighbors. I’ve found that if kept well-fed & lots of space to roam/hide, they are able to co-habitate and thrive. Our male brown anole daily courts the green female with great interest she does not return, so yes, I can certainly see how hybrid lizards are possible, and in some cases, probable. Thank you for posting your findings & producing a valuable source of info for hobbyists like myself.
Steven A. Nole
I could be viewing the past through a lens of nostalgia, but I remember the green anoles of my youth having smaller eyes as a rule; and in the case of mature males, longer snouts. The ones I see now often have larger eyes and shorter snouts, like anolis sagrei. It only takes one successful hybridization event for genes to transfer from one species to another, I suspect more than one has taken place.
Antoinette Keen
with your knowledge, can you tell me why some of the younger brown anoles have red heads? is very odd, but only the top of the head is a rust color. could it be a stage of growth?
Steven A. Nole
Florida and the southeastern lowcountry, or what I call greater Florida, is a brown anole melting pot with different races or subspecies from different Caribbean islands mingling and hybridizing here.
Perhaps redheadedness originates from a variety of anolis sagrei other than the familiar cuban one.