Urban Dinosaurs?? How a common CA Lizard is demonstrating rapid evolution in the city..

[Silas_Sancona]

A great story discussing how populations of Sceloporus occidentalis, the ubiquitous and always charming Western Fence Lizard, which reside in human altered environments are demonstrating rapid evolution- driven changes in response to the unique range of challenges they face in such places..

https://californiacurated.com/2024/10/08/the-western-fence-lizard-the-world-of-scaly-sunbathing-acrobats/

An interesting side note:  the real time adaptive strategies noted in " urban " Western Fence Lizard populations, may also be occurring within city dwelling populations of both Ornate Tree Lizard, Urosaurus ornatus  and Desert Spiny Lizard, Sceloporus magister  here in AZ. S. magister  living near homes can be trained to accept insects straight out of hand, and have been known to come to patio doors at certain times of the day, ..much like a dog might respond when it is dinner time..

Compared to specimens one might observe far out in the desert, city dwelling Desert Spinys often possess a higher tolerate of human presence ..Allowing curious humans a closer approach before they will dart off to a safe place..  Ornates in the yard will also allow me to get much closer compared to those observed out in the field as well.

Might have to start paying closer attention to any morphological differences i notice in both of these species of lizards when seen in the yard, local parks, gardens, and other human altered places,  ...and those seen far removed from frequent human interaction while out in the desert.. 

 

[Darold Petty]

Nathan, thanks so much for posting this great article !

  The Wikipedia entry for Anna's hummingbird mentions somewhat the same response, not morphology, but  showing the bird's expanding habitat northward along the Pacific coast due to increased food resources of human plantings.

[Silas_Sancona]

On 1/28/2025 at 8:17 AM, Darold Petty said:

Nathan, thanks so much for posting this great article !

  The Wikipedia entry for Anna's hummingbird mentions somewhat the same response, not morphology, but  showing the bird's expanding habitat northward along the Pacific coast due to increased food resources of human plantings.

That idea is at least partially correct..  though ..as with any other bird that is expanding it's current range right now, X Y or Z favorable change in various climate factor is probably playing a part too..

If you look up birds like Scissor Tailed Flycatcher = a bird typically found in the Cen. Plains,  Both Painted and indigo Bunting ( also considered " eastern " Birds "  )

....and " desert " species like Vermilion Flycatcher, Inca, Common Ground, and our iconic White -winged Dove, all have been greatly  increasing their ranges in CA, vs. being " rarer " vagrants that wandered into the state only on occasion..

 Recent range expansions of Black Skimmer, Royal Tern, ..All 4 sps of Sula  that occur along the west coast of Mexico, Little Blue, Tricolored, & Yellow- Crowned Night Heron, and Reddish Egret = more examples of  sps that were greatly restricted to far S. Cal -at best-,  but are now turning up in increasing #'s around S.F Bay / further north along the coast north of Pt. Conception..



Hummingbird wise, keep your eye out for Broadbills, which appear to be expanding their range in CA as well.. Considering it's wide habitat preferences, it will likely become a common " Yard Hummer "  if it establishes new territory out there.

Last April, Xantus's Hummingbird, a species currently restricted to Baja Sur, was recorded in Bishop ..A first record for CA,  2nd record north of Baja since one was observed up near Vancover,  back in '97.

 

[Darold Petty]

My garden has fledged four Anna's chicks in the past three years, and I have an active nest now in the middle of my patio.

( Somewhat inconvenient, as I hesitate to move around there, fearing that she might abandon the nest.  Guess I will just work in the front yard for the next few weeks !)   

[Silas_Sancona]

44 minutes ago, Darold Petty said:

My garden has fledged four Anna's chicks in the past three years, and I have an active nest now in the middle of my patio.

( Somewhat inconvenient, as I hesitate to move around there, fearing that she might abandon the nest.  Guess I will just work in the front yard for the next few weeks !)   

We had two that would nest each year where people traffic was heavy where i'd worked in San Jose..  One always nested on a beam above where we kept Ferns and other shade 1gal stuff.

Other would nest in whatever 25gal Camellia was placed near where the hanging Fuschias were located..

As long as they didn't get closer than approx. 6ft of each nest, neither cared about all the curious human faces that would stop to look at the nests / babies as they grew, or the constant shuffling of plants on the benches below..