Awarded / earned February 25, 2025.
My favorite Santa elf giving me a haircut in anticipation of the Christmas season.
I haven't had a haircut in a barbershop since February / March, 2020, the month the Covid-19 lockdown began. That was almost five years ago.
This was the last night Sophia and Olivia were together before Olivia headed off to college!
Tuesday, September 10, 2024 -- last night together in Euless, TX.
Sophia, age 10.
Olivia, age 18.
September 11, 2024: Olivia boards airplane to fly to SFO -- San Francisco, CA, and then ubers to Stanford.
Truly a bittersweet evening.
Wow, I already miss Olivia more than you can imagine.
To be added to Sophia's "15-minute binder."
Taxonomy.
I was curious, again, on the evolution and taxonomy of reptiles and dinosaurs.
We'll sort that out later but it got me to thinking about how to "teach" kids about evolution, how to help them remember how things happened. Or something along that line.
A reminder: phylum vs clade.
Occasionally one will run into the word, paraphylum.
What is important to animals? What is important to animals may be one way to "track" animals.
So, what's important to animals?
So, with chordata -- jaws -- feeding: link here.
Most vertebrates, including humans, evolved from jawless fish which roamed the oceans 420–390 million years ago. Acquiring jaws allowed our ancestors to bite and chew, expanding the range of food they could eat and where they could live. Understanding how this mouth structure arose is therefore a central question in evolution.
Studies in lampreys and hagfish, the only species of jawless fish that still exist today, suggest that the jaw evolved from a pre-existing skeletal system surrounding the mouth and throat that was used for filtering food and breathing. A key step in this process was the acquisition of a mobile joint, essentially a skeletal hinge that can open and close the mouth.
For this to happen, cells within the jaw skeleton – most likely cartilage cells – had to alter their gene expression to become more flexible. Such changes often involve enhancers, regions of DNA that control when a nearby gene is expressed, and in which part of the body.
Evolution of fish: wiki.
During the Devonian period a great increase in fish variety occurred, especially among the ostracoderms and placoderms, and also among the lobe-finned fish and early sharks.
This has led to the Devonian being known as the age of fishes. It was from the lobe-finned fish that the tetrapods evolved, the four-limbed vertebrates, represented today by amphibians, reptiles, mammals, and birds.
Transitional tetrapods first appeared during the early Devonian, and by the late Devonian the first tetrapods appeared.
The diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth; but it is unclear if the advantage of a hinged jaw is greater biting force, improved respiration, or a combination of factors.
Chordates -- phylum Chordata
Three subphyla:
Fish: jawless vs jawed
Amphibian: movement to land
reptiles: solved the "egg-problem"
Sophia and I have a lot of fun together. I would argue that Sophia is closest to her mother, but after that I may come in second, mostly because Sophia can always count on me and I always listen to her, having mostly "adult" conversations with her.
Yesterday in the car ride home from soccer practice, Sophia and I talked a lot about relationships.
It started with talking about Olivia being on the phone for 30 minutes with Will, who is away at college, a freshman, Olivia a senior in high school.
Kiri calls Olivia and Sophia to supper but Olivia is delayed -- saying she will be there in two minutes and that turns into four minutes and that turns into thirty minutes.
Sophia shows up at the table immediately. I suggested that Kiri probably gets angry with Olivia but Sophia said that her mother does not get upset. Sophia and Kiri simply have dinner without Olivia.
Sophia said that she's beginning to feel like an only child, and there's not much time left. Olivia will go off to college next year.
But Sophia says she is very, very lucky: she has two great parents and two great grandparents and one great sister (that would Arianna, not Olivia -- LOL).
Sophia loves Arianna -- except when Arianna acts like her (Sophia's) mom.
Then Sophia talked about how wonderful it was during the Covid lock down that I taught her everything: math, science, reading, everything. But Grammy taught her music and painting.
Sophia said Grammy must have gotten bored with Sophia's abilities in painting and music (I don't quite remember how Sophia phrased it -- but she was incredibly appreciative of what Grammy taught her).
We reminisced about the Covid lock down days. I asked her what her favorite painting was -- they did a painting every two to four weeks. I knew what she was going to say, and she did not disappoint. Her favorite painting was "the fox."
