What is the Definition of a Native Species?

For years I’ve been perplexed by the definition of native because it seems to vary greatly (almost as confusing as the definition of species itself – there are “species” that vary only through geography). Is native a time dependant variable? Does it refer to a pre-Columbian period? (Of course even the term “Native American” is nebulous at best – Kennewick Man).
The reason I bring up this question is that it seems logical to me that Anolis carolinensis originated in the Caribbean, specifically in Cuba. Based on the present day currents through the Florida Straights my guess would be somewhere in western Cuba. If western Cuba is indeed the point of origin, the most likely seed species would be Anolis porcatus. Possibly over hundreds of thousands of years including an ice age, carolinensis adapted to cooler and cooler temperatures and eventually established itself throughout the southeastern United States.


In 1549 Hernando D’Escalante Fontaneda found himself shipwrecked in the Florida Keys. He lived among the Calusa Indians for an extended period of time and chronicled the species that inhabited the area. Among the animals he noted he described “green and brown lizards”. These could simply be color phases of A. carolinensis or they may point to the possibility of A. sagrei or even five-lined skinks (Eumeces fasciatus) or Red tailed mole skinks (Eumeces egregius egregius). In any case, I wonder if the new Anolis genome mapping can give us a clue as to the approximate timeframe when the A. sagrei found in Florida diverged from those found in Cuba?
At this point there is no reason to believe that A. sagrei will displace A. carolinensis throughout the latter species’ range. The region’s climate will more than likely be a limiting agent for the spreading of A. sagrei. That being said I do recall as a young boy in the 1960s that A. sagrei was well established in most locations throughout south Florida. The prevailing wisdom of the adults at the time was that the “A. sagrei were killing or eating the A. carolinensis”.


There was one location that I do remember as being void of A. sagrei in the late 1960s; and that was Key Biscayne. Key Biscayne had one of the last healthy populations of five-lined skinks (Eumeces fasciatus) in south Florida. This reduction in the number of skinks in south Florida was largely caused by habitat destruction and development (manicured lawns vs. leaf litter and rotting logs). An interesting fact about this is that on Key Biscayne the skinks dominated the ground and trunk-ground environment. While skinks are not an Anolis species they do fill similar niches in the ecosystem.

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22 Comments

  1. Martha Munoz

    To me, native vs. introduced is a matter of human-mediated introduction. It is true that “invasions” are a part of nature. It is important, however, to know which of those invasions can be traced to human action. Moreover, not all introduced species are pests.

  2. Armando Pou

    That is a logical and concise definition Martha, thank you. This field of introduced species is fascinating and also worrisome in areas where the endemic species is already scarce.

  3. Armando Pou

    A population that is interesting to me is the A. allisoni found off the coast of Honduras. Based on the currents, how in the world did they make it from Cuba? Was the founding population actually from the small islands off of Honduras? Was there a human-mediated event sometime in history?

    • Martha Munoz

      I am not aware of a human-mediated event. Did you check out the recent AA post on these islands? Link here: https://www.anoleannals.org/2012/04/17/the-bay-islands-and-cayos-cochinos-of-honduras-endless-potential-for-future-anole-research/

      I also just took a peek at the book by McCranie et al. (2005) – Amphibians and reptiles of the Bay Islands and Cayos Cochinos, Honduras. There is no mention of a human-mediated introduction of A. allisoni, as far as I can tell.

      • Armando Pou

        Thanks Martha, I did see the recent AA post on the islands off of Honduras, but will have to check out that text by McCranie et al. (2005). I observed a dozen or so specimens of A. allisoni, including four large males among a nearby bank of red mangroves on the tourist island of Roatan. (while my family was enjoying the beach, LOL). One feature that struck me was that the adult male allisoni from this population exhibited significantly less blue than the specimens from Cuba. Maybe Native Americans liked the colors and introduced some several centuries ago! :))

      • Although it’s difficult to imagine A. allisoni moving between Cuba and Honduran islands on existing currents, West Indian ocean currents have changed over time (Hedges 2001). Hurricanes could also facilitate overwater dispersal and occasionally move in opposition to prevailing currents (see Hurricane Lenny – Fig 5, page 237, Hedges 2006).

  4. Pat Shipman

    In my view, “native” is a vague word for”indigenous” or “endemic”. When I use the latter two terms, I am referring strictly to a species that arose (evolved) in the area to which it is endemic. Thus, if A. porcatus went from Cuba to Florida, and there evolved into A. carolinensis, then A. carolinensis is indigenous (endemic) to Florida. Genomic studies can give you a broad estimate of divergence dates, but these often vary by, oh, say, 500,000 years. So genetic dates are not dates in the strict sense but estimates of divergence time, which depends on what well-dated fossils you have that you are using to calibrate how fast genetic changes arise in that lineage. Does that hel?

  5. Pat Shipman

    Ahem. Should have proofread. the last word in my post is “help.”

  6. It seems to me that “introduced” is not really an opposite to “native”. Rather, “introduced [by humans]” is one of several types of “nonnative”. (And it’s certainly not very useful term for human populations.)

    I think of “nativeness” as a sliding scale, not a discrete category. An organism is more native to a region the longer it’s had ancestors in it.

  7. Armando Pou

    Thank you Pat. Yes, that does help.
    I guess that also means that given enough time and genetic isolation from the originating population all species should evolve in adaptation to their environment.

  8. Liam Revell

    Pat, I think native & indigenous can be properly synonymized, but endemic means something different. Specifically, I would generally agree with Martha’s definition of native: a species that is “native” to a region is one that finds itself there via natural processes and without human intervention. Endemic, by contrast, refers to a species that is found exclusively in a region, and nowhere else. For instance, Anolis sagrei is native to the Bahamas, but it is not endemic as the species is also found in Cuba.

    Sometimes it can be unclear whether a species should be properly considered native/indegenous or non-native. For instance, cattle egret (now found pantropically) are thought to have dispersed naturally to the Americas from Africa in the early 20th century; however, due to their commensal relationship with large mammals, they most likely only established in the New World due to the introduction of cattle farming to the tropical Americas. Should they be considered a species indigenous to the neotropics because they dispersed naturally and with no human assistance, or are they non-native because cattle egrets only established due to human mediated changes to the environment?

    • Pat Shipman

      It’s fair enough to make a distinction such as you suggest between endemic and indigenous. A species can be one without the other.

  9. Armando Pou

    I love this topic, thank you all for your inputs and ideas!

  10. Armando Pou

    Cattle egrets, talk about Anolis eating machines! Forget sagrei, I shudder to think of their impact on Anolis species if they became established on smaller islands like Grand Cayman.

    • Pat Shipman

      Ummm, cattle egrets are established on Little Cayman, a much smaller island than Grand Cayman. Yes, they eat anolis, but we still have lots of A. manardi & A. sagrei despite them.

  11. Armando Pou

    Good to know! Maybe their impact is limited to ground-trunk species. I sat and watched one bird scarf down more than 20 Anolis sagrei in my yard one morning. Still have tons of Sagrei. Just figured that a reduced habitat might place the Anolis in peril.

  12. Geez, does nobody read my papers:) Perhaps the title of my paper on the origins of carolinensis relatives throughout the Caribbean – Out of Cuba: overwater dispersal and speciation among lizards in the Anolis carolinensis subgroup – was too cryptic?

  13. I also posted here previously about what the molecular phylogenetic data tells about carolinensis’s origins.

    • Armando Pou

      Rich, Excellent information, and a fantastic paper! Thank you for sharing it.

  14. You seem to be confusing the Five-lined Skink (Eumeces/Plestiodon fasciatus) with the very similar Southeastern Five-lined Skink (Eumeces/Plestiodon inexpectatus). The Five-lined Skink’s distribution extends only into the northern part of Florida; it has never been found as far south as the Keys. The Southeastern Five-lined Skink, on the other hand, does occur all the way to the southern tip of Florida.
    And with respect to Key Biscayne specifically, I saw a Southeastern Five-lined Skink at Bill Baggs State Park when I was there in 2010.

    • Armando Pou

      William, you are undoubtedly right, I’m not even sure if I could tell the difference between the two subspecies of five lined skinks. What I can tell you is that skinks were so common on Key Biscayne in the 60s that my friends and I had competitions when we would first get there in the mornings to see how many we could catch (we would then released them after the count). One morning I remember capturing 36, just by myself (it was the same morning I came across the largest Eastern Diamondback Rattlesnake I had ever seen). There were also a modest number of Six-lined Racerunners (A. sexlineata). Now both lizards still exist throughout south Florida but are much, much, rarer.
      Reef geckos (two different morphs) were also fairly common on Key Biscayne. On Key Biscayne unlike the rest of south Florida, rather than habitat alteration, I believe that the introduction of Ameiva ameiva led to the decline of the five lined skinks. Just in non-native Anolis, Key Biscayne now has 6 or 7 species.

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