This Mural Was Donated By The SNC’s Artist In Resident. It Shows A Typical Florida Habitat Full Of

Mesozoic Monthly: Champsosaurus

Good news everyone: it’s September! We’ve made it to month nine of 12! Sometimes it feels like this year will never end. I take comfort in the idea that if life can survive the traumatic Cretaceous-Paleogene (K-Pg) extinction that killed the non-avian dinosaurs, I can make it through 2020. One of the survival champs of the K-Pg extinction was Champsosaurus, a superficially crocodile-like reptile belonging to the extinct group Choristodera.

The skeleton of Champsosaurus laramiensis looks superficially like that of a crocodilian, but this is the result of convergent evolution. Choristoderes (like Champsosaurus) and crocodilians lived contemporaneously for at least 150 million years, until the choristoderes said “after a while, crocodile!” and went extinct. Photo by Triebold Paleontology, Inc., used with permission.

The class Reptilia encompasses an incredible variety of animals: lizards, snakes, turtles, crocodilians, pterosaurs, dinosaurs, and even birds are just a few of its members. In addition to the familiar reptiles that live today, many other reptile groups thrived for millions of years before eventually going extinct. It’s easy to think of dinosaurs like Tyrannosaurus or Triceratops when we talk about extinct reptile groups, but in reality, many extinct groups of animals with no living relatives escape the public eye. Choristodera, an order within the class Reptilia, is one of these groups. Choristoderes were semi-aquatic or aquatic carnivorous reptiles that evolved during the Mesozoic Era (the Age of Dinosaurs) and died out in the Cenozoic Era (the Age of Mammals). Just because they went extinct does not mean they were unsuccessful; the group survived for at least 150 million years! Like many animals, a rapidly shifting environment was probably the source of their demise. Until that point, choristodere evolution was able to ‘keep up’ with the changing times, including the monumental global changes that came with the K-Pg extinction. The combination of a massive asteroid impact in what’s now Mexico, extensive volcanic activity in India, and worldwide climatic shifts resulted in the extinction of over 75% of all species. Research on choristodere teeth suggests that they beat the odds by adapting to new prey.

When you think of an aquatic carnivorous reptile, you probably think of a crocodilian – and that’d be right! The crocodilian body plan is a very successful build for hunting prey in the water. As another aquatic carnivorous reptile, Champsosaurus evolved similar traits. This is an example of convergent evolution, in which unrelated species develop similar characteristics to deal with comparable circumstances. (You can read about more examples of convergent evolution in the January edition of Mesozoic Monthly about the sauropodomorph dinosaur Ledumahadi.) Some of the shared features between Champsosaurus and crocodilians include long, muscular jaws for catching fish, eyes at the top of the head for peering out of the water, and a flattened tail that was paddled side-to-side for propulsion. Of course, Champsosaurus and the rest of the choristoderes had many features that set them apart as well. Unlike crocodilians, which have bony armor called osteoderms embedded in their skin, choristoderes just had skin covered with tiny scales. In addition, crocodilians have nostrils on top of their snouts so that they can breathe while lurking beneath the surface of the water; choristodere nostrils were at the end of their snouts, so that they could stick the tip of their nose out of the water like a snorkel and breathe from down below.

A right dentary (tooth-bearing lower jaw bone) of Champsosaurus sp. from the Upper Cretaceous of Wyoming in Carnegie Museum of Natural History’s Vertebrate Paleontology collection (specimen number CM 96509). The bone is facing upwards, so you’re looking down on the teeth. Check out the dark ‘stripes’ on the enamel of each tooth. These unusual enamel striations are a hallmark of neochoristoderes, the particular choristodere subgroup to which Champsosaurus belongs. Photo by Joe Sawchak.

The traits we see in the skeleton of Champsosaurus help paleontologists paint a picture of its behavior. Instead of lurking at the surface of the water, Champsosaurus would wait on the bottom of a shallow lake or stream for prey to come close, lifting the tip of its snout out of the water to breathe. When a tasty fish approached, it would spring off the bottom with its powerful legs and snatch it with its toothy jaws. Despite having strong legs, Champsosaurus was not adapted to a terrestrial lifestyle. In fact, adult males may not have been able to leave the water at all! Fossils attributed to females have more robust hips and hind limbs, allowing them to crawl onto land to lay eggs. According to this hypothesis, the less-robust males would have been restricted to an aquatic-only lifestyle.

Some of the freshwater environments that Champsosaurus inhabited were relatively cold, but that wasn’t a big deal; choristoderes may have been able to regulate their body temperature (a talent known as endothermy or ‘warm-bloodedness’). Crocodilians, by contrast, live in warm, tropical habitats because they are not capable of regulating their body temperature and rely on the sun to warm their bodies (aka ectothermy or ‘cold-bloodedness’). This would explain why choristoderes were able to live further north than crocodilians. However, it seems that crocodilians had the right idea; temperatures around the tropics change less during cooling and warming periods than those at higher latitudes. So, when the current Antarctic ice sheets began to form and the planet started cooling, the temperate choristoderes had to deal with more environmental change than the tropical crocodilians, and finally went extinct. I think the moral of the story is, we would all be handling 2020 better if we lived in the tropics!

Lindsay Kastroll is a volunteer and paleontology student working in the Section of Vertebrate Paleontology at Carnegie Museum of Natural History. Museum staff, volunteers, and interns are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

We’re still riding the glories of Fat Bear Week and figured it would be great to take this FRIDAY to celebrate #435 aka Holly, who won last year.

Happy Friday, folks. <3 Stay safe. Stay healthy. Stay kind. Wear a mask. Be rad. <3

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Photos from the US National Park Service

NEW ECOTYPE NEW ECOTYPE NEW ECOTYPE

This African Spur Thigh Tortoise is named Bubba and he is a permanent resident at the Sawgrass Nature Center. He was previously kept as a pet, but his owners did not realize that he would get this large. And since he is an exotic species to Florida, he is non-releasable. 

The African Spur-Thigh is a native species of tortoise to Northern Africa, specifically along the southern edge of the Sahara Desert. They dig burrows in the ground to spend the hottest parts of the day in. This is known as aestivation. 

Fun fact: The African Spur Thigh Tortoise is the third largest tortoise in the world. Surpassed only by the Galapagos Tortoise and the Aldabra Giant Tortoise. 

Hi! My name is Abby De la Rocha and I am the Volunteer Coordinator at the Sawgrass Nature Center and Wildlife Hospital in Coral Springs, Florida. I was born in Puerto Rico and lived there until my family moved to Botswana when I was 8 years old. I returned to Puerto Rico when I was 16 and finished high school in Ponce. I then moved to New Orleans where I studied at Loyola University. I have been in Florida since 2006.

In this post, I’m going to tell you about Hispanic Heritage month as well as some interesting facts about Puerto Rico’s agriculture and its most precious ecosystem El Yunque.

What is Hispanic Heritage Month?

Each year, we observe National Hispanic Heritage Month from September 15 to October 15 by celebrating the histories, cultures, and contributions of American citizens whose ancestors came from Spain, Mexico, the Caribbean, and Central and South America.

This year’s Hispanic Heritage Month theme- Hispanics: Be Proud of Your Past, Embrace the Future – invites us to embrace our backgrounds, to be proud of who we are and where we came from.

Embracing the Future

The future of agriculture in Puerto Rico

Currently, Puerto Rico imports 85% of its food. This is a huge vulnerability for an island with a population of 3.1 million. For several years, my family has been involved in the agroecological movement which seeks to increase the self-sufficiency of Puerto Rico through their agricultural project Finca El Reverdecer. This movement has been largely spearheaded by young people who are eager to make a difference. I believe that by looking at our past we can create a better future.

The present agricultural reality of Puerto Rico can be traced back to Puerto Rico’s history as a Spanish colony and later as a Commonwealth of the United States. The establishment of the monoculture of sugarcane meant that many Puerto Ricans worked on sugarcane plantations. My grandfather worked cutting cane during his youth. Later, he would go on to own land that he cultivated for his own consumption. At the age of 93 he continues to enjoy getting his hands dirty on my parents’ farm.

Eventually, the sugarcane industry on the island collapsed. Its demise was due to various factors including hurricanes that decimated the island as well as policies imposed by the Federal Government. In particular, a land tax imposed in 1901 known as the Hollander Bill. As a result of this bill, many local farmers were forced to sell their land. This eventually led to mass migration from the island to the mainland. It also led to a decrease in farming in general as people did not have land to farm. Subsequently, attitudes towards farming became unfavorable, especially among young people. This is changing. Today, many small farms produce high-quality products that are sought out by individuals and restaurants alike. While still a work in progress, the path to agricultural self-sufficiency is being forged.

Celebrating the only U.S. National Forest located on an island

The El Yunque National Forest is the only tropical rainforest in the national forest system.  At nearly 29,000 acres, it is one of the smallest in size, yet one of the most biologically diverse.

The United States Department of Agriculture Forest Service. (2020) describes El Yunque, “Caressed by gentle easterly winds the forest has an average temperature of 73° F, and seasonal changes are almost imperceptible. It is the ideal climate for exuberant tropical vegetation. The rain forest is noted for its biodiversity; it is “home” to thousands of native plants including 150 fern species, 240 tree species (88 of these are endemic or rare and 23 are exclusively found in this forest). The El Yunque National Forest has no large wildlife species, but hundreds of smaller animals abound in this gentle forest, many of which exist nowhere else on the planet.”

To embrace the future, we must plan and prepare for it. Looking forwards requires us to look back at our history so that we can make sense of our present. Puerto Rico’s future is being planned by those who work the land in order to provide food for its people as well as those who work to preserve the natural wonder that is El Yunque National Forest.

If you’d like to learn more about some of the agricultural projects on the island check out the links below:

Proyecto Agroecologico el Josco Bravo

Organización Boricuá de Agricultura Ecológica de Puerto Rico

El Departamento de la Comida

Finca El Reverdecer

References:

Charles, D. (2017, May 13) How Puerto Rico Lost Its Home-Grown Food, But Might Find It Again. NPR. Retrieved from https://www.npr.org/sections/thesalt/2017/05/13/527934047/how-puerto-rico-lost-its-home-grown-food-but-might-find-it-again

U.S. Census Bureau (2019). Quick Facts Puerto Rico. Retrieved from https://www.census.gov/quickfacts/PR.

The United States Department of Agriculture Forest Service. (2020) About the Forest. Retrieved from https://www.fs.usda.gov/main/elyunque/about-forest

Dick, D. L. (2015) U.S. Tax Imperialism in Puerto Rico. American University Law Review. Retrieved from http://www.aulawreview.org/us-tax-imperialism-in-puerto-rico/#_ftn220

https://sawgrassnaturecenter.org/2020/09/29/hispanic-heritage-month/

This injured Burrowing Owl was brought to the nature center by a concerned Broward County resident to be rehabilitated. We were able to successfully able to release it back into the wild as good as new! 

This Burrowing Owl had an interesting feature that made it a unique visitor at our hospital. Most Burrowing Owls have bright yellow eyes. This one in particular possessed a recessive gene that gave it brown eyes instead. 

Our resident red rat snake has been with us for quite a few years now. He was brought to the SNC because he has a chronic neurological disease that prevents him from surviving on his own in the wild. The typical life span of red rat snakes in the wild is six to eight years. However, because this guy is getting a high grade diet and medical care, his lifespan is expected to be extended. 

What is Climate?

Climate is a long-term state that helps us predict our weather. For example, Florida’s climate isn’t going to be anything like Alaska’s. We know, as Floridians, that our climate here is sub-tropical. Our proximity to the equator and the fact that we are almost completely surrounded by water means that we typically have warmer, wetter weather. Climate is long-term and weather is short-term. Even though Florida can get the occasional cold front and thus cold weather, we know that it will eventually give way to warmer weather. Our tropical climate here in Florida is the reason we can go swimming in December.

What is climate change?

Climate change typically refers to the Earth’s total climate. Since climate is such a long-term, broad concept, it can take a lot of things and a really long time to drastically change it. However, the effects of climate change can be felt as they gradually increase overtime. For example, there were more named storms in 2020 than in any previous recorded year.

What is causing climate change?

Historically, Earth’s climate has always gradually changed over time. What’s new is the rate at which our climate is changing. Climate scientists believe this rapid change is due to the massive increase in burning fossil fuels since the Industrial Revolution. Burning fossil fuels for energy to power our homes, jobs, and cars releases gas into the atmosphere. The same atmosphere that traps air for us to breathe has been trapping the increased amounts of fossil fuels which is causing a massive shift in how we experience climate and weather.

What can I do?

Learning is always the first step. Making educated decisions for yourself and your family is the best way to move forward in any given scenario. Climate change is no different. Take the time to learn more and share the knowledge. Pasted below is a list of reliable resources on climate change.

NASA: https://www.nasa.gov/audience/forstudents/k-4/stories/nasa-knows/what-is-climate-change-k4.html

United Nations (UN): https://www.un.org/en/sections/issues-depth/climate-change/

National Oceanic and Atmospheric Administration (NOAA): https://www.noaa.gov/education/resource-collections/climate/climate-change-impacts

Check out part 1 of our Climate Change interview with Coral Springs Commissioner Nancy Metayer https://anchor.fm/snc-wild/episodes/Interview-with-Commissioner-Metayer-Part--I-eqtv93

Bees are necessary pollinators for our natural environment. Without them, majority of the plants we that produce oxygen we need to breathe wouldn’t be able to survive. A world without bees is no world indeed. 

As part of our efforts to help slow the alarming rate at which bees are dying out, the Sawgrass Nature Center is 4.5 acres of nationally certified wildlife habitat. Part of that means we host many pollinator gardens. We even have our own apiary. 

Check out how you can turn your backyard into a certified wildlife habitat here: https://www.nwf.org/garden-for-wildlife/certify

And stay updated with our social media to learn more about the SNC’s own beehives and gardens. 

I’ve said it before, and I’ll say it again: WILDLIFE REHABBERS ROCK! This nestling hawk was found on the ground at my work, we scooped him/her up, and got him to a rehabber in about an hour. The dedication to wild critters is remarkable, and it’s pretty impressive how people make themselves immediately available for the sake of animals.