Life Through Geologic Time

I'm just a Paleobiology major trying to share the beauty of the past, praise silt, and all of its wonders yet to be uncovered.

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Catching Elephant is a theme by Andy Taylor

 

Paranthropus

Paranthropus (beside human)was one of our relatives, but we don’t descend directly from it, it is one of the many shoots on the “bush” of hominids. They are referred to as the robust australopithecines and as nutcracker men. They are often called nutcracker men because of robust craniodental anatomy, including a large, gorilla-like cranial crest (which suggests strong muscles of mastication,) and large teeth. All species of Paranthropus were bipedal, and lived in times where the genus Homo (that’s us and our ancestors (i.e. Homo erectus)) were prevalent.

Paranthropus had quite different behavior from the genus Homo. It wasn’t as adaptable as Homo. It had a very specialized diet of grubs and plants, which would have made it more reliant on favorable environmental conditions. This is likely why it went extinct, the environment changed, and it couldn’t adapt. 

Skull:

By Durova (Own work) [GFDL (www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

Bust:

By Photographed by User:Lillyundfreya [GFDL (www.gnu.org/copyleft/fdl.html), CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0/) or CC-BY-SA-2.5-2.0-1.0 (www.creativecommons.org/licenses/by-sa/2.5-2.0-1.0)], via Wikimedia Commons

Living Fossils - Queensland Lungfish The Queensland Lungfish is the only surviving member of its Family, Ceratodonitidae, and the Order Ceratodontiformes. That doesn’t mean that there aren’t other lungfish, though! There are six extant species, including the Queensland Lungfish.  The Queensland Lungfish is a lobe-finned fish, sometimes called fleshy-finned fish, which is interesting enough because Tetrapoda descended from Sarcopterygii (Lobe-finned fish.) (Remember, evolution isn’t progress, it’s diversification through change through decent.) (See Tiktaalik song) It is one of the six extant species of Dipnoi (lungfishes) which flourished during the Devonian, and is the most primitive surviving member of Dipnoi. It can survive out of water for several days, but, unlike its four African cousins, it cannot survive total water depletion and must be kept moist. Fossils almost identical to the Queensland Lungfish have been found, indicating that it has remained nigh unchanged since 100 mya , and, therefor, is a viable living fossil.

Living Fossils - Queensland Lungfish

The Queensland Lungfish is the only surviving member of its Family, Ceratodonitidae, and the Order Ceratodontiformes. That doesn’t mean that there aren’t other lungfish, though! There are six extant species, including the Queensland Lungfish. 

The Queensland Lungfish is a lobe-finned fish, sometimes called fleshy-finned fish, which is interesting enough because Tetrapoda descended from Sarcopterygii (Lobe-finned fish.) (Remember, evolution isn’t progress, it’s diversification through change through decent.) (See Tiktaalik song) It is one of the six extant species of Dipnoi (lungfishes) which flourished during the Devonian, and is the most primitive surviving member of Dipnoi. It can survive out of water for several days, but, unlike its four African cousins, it cannot survive total water depletion and must be kept moist. Fossils almost identical to the Queensland Lungfish have been found, indicating that it has remained nigh unchanged since 100 mya , and, therefor, is a viable living fossil.

Alright, friends, let’s talk about evolution. FIRSTLY, I MUST SAY THIS, AND I MUST SAY IT IN BOLD AND CAPS LOCK, THE ABOVE PICTURE IS NOT EVOLUTION, IT IS AN ACCIDENT THAT LIKELY AROSE FROM THIS IMAGE:  Now that that’s said, let’s talk about evolution, and its process, natural selection. Evolution: Evolution is change with descent. Now what does that mean, “change with descent”? Well, change with descent is just how organisms change genetically with descent, that is, how organisms’ offspring change from the organisms which they arose from. IT IS NOT “PROGRESS,” AND IT IS FOOLISH TO THINK IT IS, EVOLUTION IS THE ADAPTATION TO A LOCAL AND CHANGING ENVIRONMENT, OR, MERELY, GENETIC CHANGE WITH DESCENT (as stated (repeatedly) above.) Natural Selection: Contrary to what many believe, Natural Selection is not the same as Evolution. Natural selection follows three relatively undeniable principles, which are as follows: Variation: Life varies. Whop-dee-doo. I am different from every other Homo sapiens sapiens and there’s nothing you can do about it. Coincidentally, I am also different from every armadillo, but we’ll talk about that later if you’re good. Heredity: When a mommy and a daddy get “it” on, and their genes cross and get together, they make a new sequence that probably never existed before then. This is, of course, true only for organisms that sexually reproduce. Occasionally asexual organisms will make babies with themselves, but this doesn’t usually yield any genetic change. When it does, however, whoop-dee-doo, we have a new organism that has a new DNA sequence Superfecundity: I particularly like this principal because it’s fun to say and is, some might say, a bit morbid. Superfercundity is the principle that more offspring are produced than could ever possibly survive to adult hood and mate to make more little organisms.  The Inference: The inference is that, on average, the organisms better suited for their local and changing environment will survive to pass on their traits, but not necessarily, as something may happen to an organism, it could fall off a cliff, be run over by a car, be attacked by a starving horde of flesh eating slugs, et cetera. If said organism does pass on its genetics, the offspring will, on average, look similar to the parents, yet different.

Alright, friends, let’s talk about evolution. FIRSTLY, I MUST SAY THIS, AND I MUST SAY IT IN BOLD AND CAPS LOCK, THE ABOVE PICTURE IS NOT EVOLUTION, IT IS AN ACCIDENT THAT LIKELY AROSE FROM THIS IMAGE: Huxley - Man's Place in Nature Now that that’s said, let’s talk about evolution, and its process, natural selection.

Evolution:

Evolution is change with descent. Now what does that mean, “change with descent”? Well, change with descent is just how organisms change genetically with descent, that is, how organisms’ offspring change from the organisms which they arose from. IT IS NOT “PROGRESS,” AND IT IS FOOLISH TO THINK IT IS, EVOLUTION IS THE ADAPTATION TO A LOCAL AND CHANGING ENVIRONMENT, OR, MERELY, GENETIC CHANGE WITH DESCENT (as stated (repeatedly) above.)

Natural Selection:

Contrary to what many believe, Natural Selection is not the same as Evolution. Natural selection follows three relatively undeniable principles, which are as follows:

Variation: Life varies. Whop-dee-doo. I am different from every other Homo sapiens sapiens and there’s nothing you can do about it. Coincidentally, I am also different from every armadillo, but we’ll talk about that later if you’re good.

Heredity: When a mommy and a daddy get “it” on, and their genes cross and get together, they make a new sequence that probably never existed before then. This is, of course, true only for organisms that sexually reproduce. Occasionally asexual organisms will make babies with themselves, but this doesn’t usually yield any genetic change. When it does, however, whoop-dee-doo, we have a new organism that has a new DNA sequence

Superfecundity: I particularly like this principal because it’s fun to say and is, some might say, a bit morbid. Superfercundity is the principle that more offspring are produced than could ever possibly survive to adult hood and mate to make more little organisms. 

The Inference: The inference is that, on average, the organisms better suited for their local and changing environment will survive to pass on their traits, but not necessarily, as something may happen to an organism, it could fall off a cliff, be run over by a car, be attacked by a starving horde of flesh eating slugs, et cetera. If said organism does pass on its genetics, the offspring will, on average, look similar to the parents, yet different.

First order of business, how I studied for my geology final.

rhamphotheca: Mysterious Ancient Creature Discovered (May 2010) by Brett Israel It’s not the mythical kraken, but an ancient creature belonging to the largest, nimblest and probably smartest group of invertebrates has jumped out of the fossil record with a different identity than previously thought. That finding restructures a branch on the evolutionary tree. The tiny mysterious fossil of Nectocaris pteryx — previously described as a shrimp with a chordate tail — is neither a shrimp (an arthropod) nor a chordate (vertebrates and their nearest relatives), but a mollusk, according to a new study detailed in the May 27 issue of the journal Nature.  Don’t picture boring mollusks, such as snails, slugs and mussels, however. Think cuttlefish, squid, and octopi — and yes, even the kraken — which are cephalopods, a member of the mollusk phylum. The 505 million-year-old creature is the oldest recorded cephalopod by about 10 to 15 million years and provides clues about modern cephalopod evolution… (read more: Live Science)   (image: )

rhamphotheca:

Mysterious Ancient Creature Discovered (May 2010)

by Brett Israel

It’s not the mythical kraken, but an ancient creature belonging to the largest, nimblest and probably smartest group of invertebrates has jumped out of the fossil record with a different identity than previously thought. That finding restructures a branch on the evolutionary tree.

The tiny mysterious fossil of Nectocaris pteryx — previously described as a shrimp with a chordate tail — is neither a shrimp (an arthropod) nor a chordate (vertebrates and their nearest relatives), but a mollusk, according to a new study detailed in the May 27 issue of the journal Nature. 

Don’t picture boring mollusks, such as snails, slugs and mussels, however. Think cuttlefish, squid, and octopi — and yes, even the kraken — which are cephalopods, a member of the mollusk phylum. The 505 million-year-old creature is the oldest recorded cephalopod by about 10 to 15 million years and provides clues about modern cephalopod evolution…

(read more: Live Science)   (image: )

(Source: deusesastronautas)