Science Monday - Review of Meeting on April 10, 2023

Hoping that you are well, we’ll briefly review the April 10^th meeting. Attending were Sharon, Barbara. Dick, Karen and Bob. We had presentations on two areas: Barbara gave us two somewhat related areas to consider-a. how climate has shaped migration of plants, animals and humans over the eons and how the brain has a low power mode if nutritionally or otherwise depleted, in which some details of perception are lost.

First of all, I hope that you are used to hearing is influenced by genes but not by genes alone. For example, the massive asteroid that smashed into the earth about 66 million years ago. It was tens of miles wide and started fires all over the planet, An asteroid, perhaps knocked off course by Jupiter, came very near to the sun and broke into fragments- it struck the earth near Yucatan and left the huge undersea crater, Chicxulub. Genetics as we understand it was not a cause of this impact which killed off about 70% of all life. But genetic endowment was important in determining which species survived. In the same fashion, temperature and atmospheric conditions influence life, evolution and the distribution of life but weren’t the only factors.

I will focus on the upcoming meeting today at 4 PM, which I will attend. As always the world is full of science news, some genuine, some confusing or hard to interpret, and some false. Our meeting can be helpful if you learn of doubts about an item of Science news or we learn that it is much more complex than discussed in the media. I will present some material on comb jellies and hypothetical trees of life, but the bulk f the meeting is for you, not me.

This afternoon, our meeting is at 4 PM. I hope that many of you can come and bring items for discussion. The Zoom code for our meeting is listed below, sent from Hannah Rough-Shock. We welcome newcomers who want to see how our meetings work out.

consciously named his tree after the biblical Tree of Life, as described in Genesis, thus relating his theory to the religious tradition.^[8]

Page from Darwin's notebooks (c. July 1837) with his first sketch of an evolutionary tree, and the words "I think" at the top

Diagram in Darwin's On the Origin of Species, 1859.
It was the book's only illustration. Birds

· Habitat Profiles

· Mammals

· Reptiles

· Insects

Table of Contents

· Description

· Habitat and Range

· Diet

· Behavior

· Reproduction and Offspring

· Conservation Status

· Comb Jellies and Humans

· Sources

Anne Marie Helmenstine, Ph.D.

Updated on October 15, 2019

The comb jelly is a marine invertebrate that swims by beating rows of cilia that resemble combs. Some species have rounded bodies and tentacles like jellyfish, but comb jellies and jellyfish belong to two separate phyla. Jellyfish are cnidarians, while comb jellies belong to the phylum ctenophora. The name ctenophora comes from Greek words that mean "comb carrying." Approximately 150 comb jelly species have been named and described to date.

consciously named his tree after the biblical Tree of Life, as described in Genesis, thus relating his theory to the religious tradition.^[8]