What Was Grass Before Grass?

[Gelatinous squid]

Nowadays, if there is no forest and no desert, there is grassland. But grasses have only been around for a short time, and I can't believe that before the grasses there was no plant that exploited the biome between forest and desert. But what was it?

[Auspex]

Contiguous grasslands persist because of grass; fire is its ally in curtailing woody growth. Before grasses evolved, the "zone" they now inhabit would have been filled by vegetation of the types in adjacent areas.

[Northern Sharks]

I believe things like mosses and lichens have been around much longer than grasses, as well as several types of ferns.

[bear-dog]

Anti-grass. :lol:It's on a sub atomic particulate type of thingy[you can't see it,like anti-matter].If it wasent for anti-grass the sand would float off into space.

Don't believe me?Ask tracer

Edited December 18, 2010 by bear-dog

[Fruitbat]

It would appear that non-flowering vascular plants of various types would have been the predominant ground cover in the pre-grass ages. Until recently, grasses were thought to have evolved in the Paleocene but recent finds of phytoliths in dinosaur coprolites seem to push the grass timeline back into at least the Cretaceous and possibly earlier.

The Earth must have been a very different-looking place in the days before the development of the flowering plants.

-Joe

Edited December 19, 2010 by Fruitbat

[Shellseeker]

Just searching the internet:

http://www.foxnews.com/story/0,2933,176052,00.html

WASHINGTON — Imagine dinosaur terrain — full of ferns and palms, right? Better add some grass to that picture.

A new discovery debunks the theory that grasses didn't emerge until long after the dinosaurs died off.

Fossilized dung tells the story: The most prominent plant-eating dinosaurs were digesting different varieties of grass between 65 million and 71 million years ago, researchers report Friday in the journal Science.

The earliest grass fossils ever found were about 55 million years old — from the post-dinosaur era.

Sounds like ferns, palms, cycads before they got that tasty grass...

Read more: http://www.foxnews.com/story/0,2933,176052,00.html#ixzz18Uh6kut2

[piranha]

It would appear that non-flowing vascular plants of various types would have been the predominant ground cover in the pre-grass ages. Until recently, grasses were thought to have evolved in the Paleocene but recent finds of phytoliths in dinosaur coprolites seem to push the grass timeline back into at least the Cretaceous and possibly earlier.

Excellent Fruitbat! I've attached two figures that point to the Late Cretaceous of Tennessee.

Can you point to the reference for the phytolith-coprolite discovery? Thanks for the great info!

EDIT: Late Cretaceous of India

RE: Paleobotany: The Biology and Evolution of Fossil Plants / 2009 Second Edition by Thomas N. Taylor, Edith L. Taylor, Michael Krings et al.

Many of the modern grass families are believed to have appeared during the early Eocene (Savile, 1987), although the fossil record is not well demonstrated before the Eocene. Crepet and Feldman (1991), however, have reported grass spikelets (fig. 22.106) with pollen from the Paleocene-Eocene of western Tennessee that suggest the existence of the Poaceae at least by the Late Cretaceous (fig. 22.107).

Edited December 18, 2010 by piranha

[Fruitbat]

piranha...

Scholarly references are not abundant for the Cretaceous appearance of grasses but I can point you to:

Barrett, P.M. and E.J. Rayfield (2006). Ecological and evolutionary implications of dinosaur feeding behaviour. Trends in Ecology and Evolution, Vol.21, Number 4. (Full Text)

Dutta, D. and K. Ambwant (2007). Capers: A Food for Upper Cretaceous dinosaurs of Pisdura, India. Current Science, Vol.92, Number 7 (Full Text)

Piperno, D.R. and H.D. Sues (2005). Dinosaurs Dined on Grass. Science, Vol. 310, Number 5751. (only abstract available for free on-line at Science AAAS)

Prasad, V, et al. (2005). Dinosaur Coprolites and the Early Evolution of Grasses and Grazers. Science, Vol.310, Number 5751. (only abstract available for free on-line at Science AAAS)

Vaughan, D.A., et al. (2008). III.1. Phylogeny and Biogeography of the Genus Oryza. In: Rice Biology in the Genomics Era, Hirano, H-Y., et al. (eds.), Biotechnology in Agriculture and Forestry, 62. (Full Text)

Hopefully these will be informative.

-Joe

[piranha]

Hi Joe and thanks for the fantastic assorted references. I discovered the Prasad paper as you were answering. It's an instructive exercise to discover the distribution and stratigraphic origin of Poaceae given the randomness and scarcity of occurrences in the fossil record.

I appreciate your superb assistance!

[Fruitbat]

My pleasure, piranha!

Now...as to the original question as posed by Gelatinous squid...it looks like, in some localities, various types of ferns might have been the predominant ground cover:

Wing, S.L., L.J. Hickey and C.C. Swisher (1993). Implications of an exceptional fossil flora for Late Cretaceous vegetation. Nature, Vol.363 (Full Text)

In other areas, coniferous forest seems to have predominated:

Falcon-Lang, H.J., R.A. MacRae and A.Z. Csank (2004). Palaeoecology of Late Cretaceous polar vegetation preserved in the Hansen Point Volcanics, NW Ellesmere Island, Canada. Palaeo, 212. (Full Text)

In their 1986 paper, Retallack and Dilcher state that angiosperms (flowering plants) appear in North America during the Cretaceous and were predominant only along coastal and fluvial (along rivers and streams) environments and that the inland areas were dominated by conifers.

Retallack, G.J. and D.L. Dilcher (1986). Cretaceous Angiosperm Invasion of North America. Cretaceous Research, 7. (Full Text)

Royer, et al. did an analysis that seems to agree with that of Retallack and Dilcher:

Royer, D.L., et al. (2010). Leaf Economic Traits from Fossils Supports a Weedy Habit for Early Angiosperms. American Journal of Botany, 97(3). (Full Text)

-Joe

[piranha]

I would be well advised to pay closer attention to your pdf repositories posted here at TFF. What a terrific synthesis of knowledge to be gleaned here in this thread. And I thought the plate was full from your previous post. How many credits are earned in completion of today's online syllabus?

Thanks Joe, you're the best!

[MOROPUS]

I have always heard that the extense grasslands around the world (like the ones in USA), appeared during the late Miocene or Pliocene. Is this exact?

[Fruitbat]

The Miocene/Pliocene (8 to 6 MaBP) expansion of the grasslands is fairly well-documented. A shift toward a drier climate during this time favored plants that use the C4 photosynthetic pathway (which is less wasteful of water) over those that employ the C3 photosynthetic pathway. C4 pathway plants (including most grasses) seem to have first appeared during the Oligocene but did not become particularly significant until the Miocene. As the extensive forests diminished, the C4 grasses outcompeted other plants and the result was the formation of extensive grassland areas (and the associated grazing faunas).

Some interesting papers that address this topic include:

Anderson, R.C. (2006). Evolution and origin of the Central Grasslands of North America: climate, fire and mammalian grazers. Journal of the Torrey Botanical Society, 133(4).

Bobe, R. and A.K. Behrensmeyer (2004). The expansion of grassland ecosystems in Africa in relation to mammalian evolution and the origin of the genus homo. Palaeo, 207.

Partel, M., H.H. Bruun and M. Sammul. Biodiversity in temperate European grasslands: origin and conservation. Grassland Science in Europe, Vol.10.

-Joe

[piranha]

On 12/18/2010 at 4:24 PM, Fruitbat said:

The Miocene/Pliocene (8 to 6 MaBP) expansion of the grasslands is fairly well-documented. A shift toward a drier climate during this time favored plants that use the C4 photosynthetic pathway (which is less wasteful of water) over those that employ the C3 photosynthetic pathway. C4 pathway plants (including most grasses) seem to have first appeared during the Oligocene but did not become particularly significant until the Miocene. As the extensive forests diminished, the C4 grasses outcompeted other plants and the result was the formation of extensive grassland areas (and the associated grazing faunas).

Some interesting papers that address this topic include:

Anderson, R.C. (2006). Evolution and origin of the Central Grasslands of North America: climate, fire and mammalian grazers. Journal of the Torrey Botanical Society, 133(4).

Bobe, R. and A.K. Behrensmeyer (2004). The expansion of grassland ecosystems in Africa in relation to mammalian evolution and the origin of the genus homo. Palaeo, 207.

Partel, M., H.H. Bruun and M. Sammul. Biodiversity in temperate European grasslands: origin and conservation. Grassland Science in Europe, Vol.10.

-Joe

I'm enjoying your explanation(s) very much. Would you please expand on your last post by elaborating about Kranz anatomy as a mechanism to interpret the fossils (phytoliths) and their paleoclimatology at a specified boundary of geologic time?

[Fruitbat]

Yegads! This is going to turn into a mini-treatise on angiosperm anatomy and photosynthesis strategies!

OK...some basics first:

Most people have learned the basic equation for photosynthesis as:

6 CO₂ + 6 H₂O + light ------> C₆H₁₂O₆ + 6 O₂ + energy

However...the process of photosynthesis is actually a complex pathway consisting of multiple chemical reactions. Basically, this process takes CO₂ molecules from the air and 'fixes' them into the more complex C₆H₁₂O₆ (glucose).

RuBisCo (ribulose-1,5 biphosphate carboxylase oxygenase) is an enzyme involved in the process of carbon-fixation wherein carbon atoms from atmospheric CO₂ are 'fixed' into glucose. In C3 plants, the efficiency of RuBisCo is reduced because some of the substrate production is lost through a process called photorespiration in which the cells fix oxygen instead of carbon. If a plant can bypass the process of photorespiration there is less substrate loss so the carbon fixation process is more efficient.

C4 plants bypass the photorespiration process by isolating the RuBisCo molecules in such a way that a very high concentration of CO₂ is maintained around the enzyme (meaning there is less oxygen available to support photorespiration). The kranz anatomy simply describes a double layer of specialized cells that help maintain the high CO₂ concentration around the RuBisCo molecules. One disadvantage of the C4 strategy is that it requires the plant to use more energy to fix the carbon in one molecule of glucose. This is mitigated by the increased efficiency of glucose production.

C4 plants have an advantage over C3 plants under conditions of drought and high temperature (often associated with high amounts of sunlight) because they are more efficient at carbon fixation and because C4 plants only lose about 1/3 as much water during the chemical processes involved in photosynthesis as C3 plants. C4 plants come into their own under high light and low moisture conditions whereas C3 plants win out in low light environments or where there is abundant moisture.

As far as fossils are concerned, if plant fossils are preserved with enough detail, it is sometimes possible to detect the specialized kranz anatomy by microscopic examination. Since only C4 plants exhibit this adaptation, a fossil that has kranz anatomy can reasonably be interpreted to have come from a high light environment and thus from an area with limited numbers of trees.

A 'fun' article in this vein is:

Connin, S.L., J. Betancourt and J. Quade (1998). Late Pleistocene C4 Plant Dominance and Summer Rainfall in the Southwestern United States from Isotopic Study of Herbivore Teeth. Quaternary Research, 50.

PHEW!!!

-Joe

Edited December 19, 2010 by Fruitbat

[Plantguy]

Joe and others, I'm thoroughly enjoying this thread---they can all say I'm sick because I am--its ok--I'm used to the plant abuse! I just wish I had enough time to read all the details that are appearing in this and the other discussions/explanations threads lately! WOW!

But please don't send the exam(s) out quite yet, I dont think the gray matter has absorbed all of it yet! I may never get there but keep it coming! Seriously, thanks again for the detailed explanation!

Regards, Chris

[Fruitbat]

Plantguy...

Plants and animals have been in continuous conflict ever since the time when the two began to co-exist on this planet. Animals have constantly evolved new ways to eat plants and plants have continuously evolved ways of preventing themselves from being eaten. This war alone makes the interaction between plants and animals a fascinating thing to study. I've always enjoyed botany...especially the study of the non-vascular plants...and I feel that you really can't have a firm understanding of animal ecology unless you have a reasonably good grasp of the basics of the way plants live. You'll NEVER hear me making fun of anybody who has a true interest in the plants!

-Joe

[siteseer]

A few years ago, I was researching the origin of grasses for a friend and I read that some herbivores in South America were already evolving high-crowned teeth, an adaptation not seen in North American mammals until the Mid-Late Miocene. Has it been determined that grasses were first successful in South America or were the high-crowned teeth a response to some other native plant?

The Miocene/Pliocene (8 to 6 MaBP) expansion of the grasslands is fairly well-documented. A shift toward a drier climate during this time favored plants that use the C4 photosynthetic pathway (which is less wasteful of water) over those that employ the C3 photosynthetic pathway. C4 pathway plants (including most grasses) seem to have first appeared during the Oligocene but did not become particularly significant until the Miocene. As the extensive forests diminished, the C4 grasses outcompeted other plants and the result was the formation of extensive grassland areas (and the associated grazing faunas).

Some interesting papers that address this topic include:

Anderson, R.C. (2006). Evolution and origin of the Central Grasslands of North America: climate, fire and mammalian grazers. Journal of the Torrey Botanical Society, 133(4).

Bobe, R. and A.K. Behrensmeyer (2004). The expansion of grassland ecosystems in Africa in relation to mammalian evolution and the origin of the genus homo. Palaeo, 207.

Partel, M., H.H. Bruun and M. Sammul. Biodiversity in temperate European grasslands: origin and conservation. Grassland Science in Europe, Vol.10.

-Joe

[Fruitbat]

Fascinating topic!

Hypsodont (high-crowned) teeth are generally associated with multiple lifestyles. The first involves animals that graze on abrasive grasses. The second involves fossorial (burrowing) animals that feed on roots that may be abrasive if they are covered by sediments. Thirdly, semi-aquatic animals that feed on roots, bark and other abrasive materials often exhibit hypsodonty. Another factor that favors hypsodont teeth involves feeding in open habitats on herbaceous plants that may be covered with airborne grit and dust (Mendoza and Palmqvist, 2007).

Mammals of the suborder Gondwanatheria are represented by relatively uncommon, fragmentary fossils but it appears that they may have been among the first mammals to develop hypsodont teeth. Sudamerica ameghinoi was an early Paleocene gondwanathere from (as the genus name implies) South America that definitely possessed hypsodont cheek teeth (v.Koenigswald, Goin and Pascual, 1999). Other gondwanatheres (like Lavanify miolaka from Madagascar and an unnamed species from India) seem to push hypsodonty back into the Cretaceous. Interestingly, Sudamerica seems to have lived in a swampy transition area and the ungulates that co-existed with it in the same area do not show any evidence of hypsodonty.

Hypsodonty doesn't really become apparent in other major groups of mammals until the Miocene when the global environment seems to have become more arid, favoring the spread of the grasslands (Stirton, 1947; Jernvall and Fortelius, 2002; Janis, 2008).

While representatives of the first truly hypsodont mammals do appear in the Paleocene of South America, this may not indicate that grasses were flourishing in that area at the time. The proposed environment of Sudamerica may tell us that it was a semi-aquatic or fossorial animal rather than being a grazer.

Articles

Janis, C. (2008). Chapter 2. An Evolutionary History of Browsing and Grazing Ungulates. In: The Ecology of Browsing and Grazing, Gordon, I.J. and H.H.T. Prins (eds.). Ecological Studies 195.

Jernvall, J. and M. Fortelius (2002). Common mammals drive the evolutionary increase of hypsodonty in the Neogene. Nature, Vol.417.

Mendoza, M. and P. Palmqvist (2007). Hypsodonty in ungulates: an adaptation for grass consumption or for foraging in open habitat? Journal of Zoology.

Stirton, R.A. (1947). Observations on Evolutionary Rates in Hypsodonty. Evolution, 1.

von Koenigswald, W, F. Goin and R. Pascual (1999). Hypsodonty and enamel microstructure in the Paleocene gondwanatherian mammal Sudamerica ameghinoi. Acta Palaeontologica Polonica, 44(3).

-Joe

[pleecan]

And before grass and before development of trees we have primitive vascularized plant from the Silurian ... this is a rare example of new species of Cooksonia (Middle Silurian)(one example of the earlier land plants) that has been describe early 2000s from the Bertie Lagerstatte, Ontario Canada.

scale =mm

PL

Edited December 19, 2010 by pleecan

[Plantguy]

Hey Joe and Piranha, thanks for all the plant support! My sound card is out at the moment so I'll have to enjoy the audio merriment when that issue is resolved. I did go to the site and it looks entertaining and intriguing.

Plant abuse is not an issue here in the forum--it's in the non fossil world that I work/live in that let's just say there is some misunderstanding about plant complexities and their relevance in the world we live in. Its really kind of a silly subject. The first time I saw and stood as a young boy next to a 300 foot tall Giant Sequoia in California I knew there was something really special going on with "them there plants" and that interest has never wavered! It's all good, there are so many other serious, much more complex issues that the world faces and needs to discuss/solve.

Anyways, Gelatinous squid, thanks for the thread topic and the spark behind these discussions!

This is probably my last post for 2010--lots of stuff going on here. Everyone have a safe holiday season. Wishing you all a Merry Christmas and a Happy New Year. Great Hunting! Talk to you again in 2011!

Regards, Chris

[siteseer]

Thanks for the info, Fruitbat. I meant to include that there were hypsodont South American mammals by the Eocene but you knew what I was talking about.

It is an interesting topic.

Fascinating topic!

While representatives of the first truly hypsodont mammals do appear in the Paleocene of South America, this may not indicate that grasses were flourishing in that area at the time. The proposed environment of Sudamerica may tell us that it was a semi-aquatic or fossorial animal rather than being a grazer.

[Fruitbat]

To all involved in this topic...this is EXACTLY the reason I joined The Fossil Forum in the first place. A forum like this gives us an opportunity to engage in the same sorts of conversations as the 'professional' paleontologists and allows us all to expand our knowledge in a wide variety of subjects. In this one topic alone we've managed to hit bits of paleoecology, botany, paleodiversity, anatomy and evolution!

LOTS of FUN!!

-Joe