Sun, 27 October 2019
The gang talks about two papers that look at potential examples of parasitism in the fossil record. One paper finds possible parasites attaching to ancient ostracods, and another paper details potential parasitic isopods on electric ray fossils. Meanwhile, James practices his spidey sense, Curt is suspicious that things are going too well, and Amanda’s internet has amazing timing.
Up-Goer Five (Amanda and James Edition): Today our friends talk about animals that eat other animals without killing them. First our friends talk about a paper that talks about an animal that has big teeth but no hard inside parts even though it is in a group that has hard inside parts and lives in the water. This animal has a number of smaller animals that have sort of hard outer parts, that may have been living on its skin by sticking its head inside its skin and living there. It is very hard to tell if this thing had its head in the animal with big teeth and no inside hard parts when it lived, or if it was just maybe eating the animal after it was dead. It is very hard to tell if things ate other things while they were still living or if they were there after it died. Our friends also talk little animals that have five arms that today live in animals without legs that breath water. The animals with five arms first became animals with five arms that ate other animals without killing before the animals without legs that breath water came to be, so we did not know what the animals with five arms used to eat. Now we know that they would eat animals with lots of legs and a hard head, and that they would eat the animals with lots of legs and a hard head from lots of places, not just inside like they eat the animals with no legs that breath water.
References: Siveter, David J., et al. "A 425-million-year-old Silurian pentastomid parasitic on ostracods." Current Biology 25.12 (2015): 1632-1637. Robin, Ninon, et al. "Eocene isopods on electric rays: tracking ancient biological interactions from a complex fossil record." Palaeontology 62.2 (2019): 287-303.
Direct download: Podcast_174_-_Feeling_Drained_Parasites_in_the_Fossil_Record.mp3
Category:general -- posted at: 3:00am EST |
Sun, 13 October 2019
The gang discusses two papers that look into early plant evolution and ecology. The first paper looks at some evidence from fossil spores to determine where the earliest vascular plants on land may have evolved. The second paper looks at a unique Devonian forest ecology from China. Meanwhile, James accidentally hoists himself, Amanda is more heard than she thinks, Curt fails as acting like everything’s ok, and everyone has a good old time working around Amanda’s computer deciding to die.
Up-Goer Five (Curt Edition): Our friends talk about old things that can make their own food from the sun. First, they talk about some of the oldest things that make their food from the sun which also have ways of moving water from the bottom of the thing to the top. Before this paper, it was thought that things which make their food and live on the land probably first started in the big piece of land that used to be made up of most of the other land pieces put together. With this paper, they found parts of these things which are used for making babies in the rocks of a different piece of land. This makes the people who wrote the paper think that, maybe, a lot of the changes in these early things on the land that make food may have actually happened in this other place. The second paper looks at some very early trees. These trees are not the same as trees today, because they are not quite doing the same thing as trees today. But these early trees still act a bit like trees today. This paper finds a very interesting type of group of trees which seems to be in a place close to the big blue wet thing. This group of trees has the trees way more close together than we have seen before. It is a lot earlier than when we usually see trees that are grouped very close together. This means that trees got very close together with a lot of trees in one area very early on. This means that the big groups of trees we see a bit later on had their start earlier than we had first thought. This group of trees is also very cool is that the way the trees are grouped together is very different from what we see today, and even in the past. The trees are all the same type of tree and there are big, not so big but not so small, and small trees all grouped together. This means that lots of trees grouped together could really pull down some clear things in the air that control how hot the air is.
References: Wang, Deming, et al. "The Most Extensive Devonian Fossil Forest with Small Lycopsid Trees Bearing the Earliest Stigmarian Roots." Current Biology 29.16 (2019): 2604-2615. Rubinstein, Claudia V., and Vivi Vajda. "Baltica cradle of early land plants? Oldest record of trilete spores and diverse cryptospore assemblages; evidence from Ordovician successions of Sweden." GFF (2019): 1-10.
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