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Consequences of the Megafauna Extinction: Changes in Food Web Networks on the Edwards Plateau Across the Pleistocene–Holocene Transition

Global Ecology and Biogeography, Volume 34, Issue 12, December 2025.
ABSTRACT Aims Today, we are experiencing rapid biodiversity loss due to climate change and human impacts. Such biodiversity loss is not only harmful to the environment but can also alter the composition of communities and the interactions of their members.
Quentin A. Smith, Catalina P. Tomé, William Gearty, Felisa A. Smith, Daizaburo Shizuka, S. Kathleen Lyons   +5 more
wiley   +1 more source

On-line Ramsey numbers [PDF]

, 2009
Consider the following game between two players, Builder and Painter. Builder draws edges one at a time and Painter colours them, in either red or blue, as each appears.
Conlon, David
core   +1 more source

Ramsey numbers of ordered graphs

, 2019
An ordered graph is a pair $\mathcal{G}=(G,\prec)$ where $G$ is a graph and $\prec$ is a total ordering of its vertices. The ordered Ramsey number $\overline{R}(\mathcal{G})$ is the minimum number $N$ such that every ordered complete graph with $N ...
Balko, Martin, Cibulka, Josef, Král, Karel, Kynčl, Jan   +3 more
core   +1 more source

Chordal Graphs, Even‐Hole‐Free Graphs and Sparse Obstructions to Bounded Treewidth

Journal of Graph Theory, Volume 110, Issue 3, Page 351-365, November 2025.
ABSTRACT Even‐hole‐free graphs pose a central challenge in identifying hereditary classes of bounded treewidth. We investigate this matter by presenting and studying the following conjecture: for an integer t ≥ 4 and a graph H, every even‐hole‐free graph of large enough treewidth has an induced subgraph isomorphic to either K t or H, if (and only if) H
Sepehr Hajebi
wiley   +1 more source

Some Exact Ramsey-Tur\'an Numbers

, 2012
Let r be an integer, f(n) a function, and H a graph. Introduced by Erd\H{o}s, Hajnal, S\'{o}s, and Szemer\'edi, the r-Ramsey-Tur\'{a}n number of H, RT_r(n, H, f(n)), is defined to be the maximum number of edges in an n-vertex, H-free graph G with ...
Balogh, József, Lenz, John
core   +1 more source

Weighted Turán Theorems With Applications to Ramsey‐Turán Type of Problems

Journal of Graph Theory, Volume 110, Issue 1, Page 59-71, September 2025.
ABSTRACT We study extensions of Turán Theorem in edge‐weighted settings. A particular case of interest is when constraints on the weight of an edge come from the order of the largest clique containing it. These problems are motivated by Ramsey‐Turán type problems.
József Balogh, Domagoj Bradač, Bernard Lidický   +2 more
wiley   +1 more source

New directions in Ramsey theory [PDF]

Discrete Mathematics Letters, 2021
Gary Chartrand, Ping Zhang
doaj   +1 more source

The k-Ramsey number of two five cycles

AKCE International Journal of Graphs and Combinatorics
Given any two graphs F and H, the Ramsey number R(F, H) is defined as the smallest positive integer n such that every red-blue coloring of the edges of the complete graph Kn of order n, there will be a subgraph of Kn isomorphic to F whose edges are all ...
Johannes H. Hattingh, Elizabeth Jonck, Ronald J. Maartens   +2 more
doaj   +1 more source

Zarankiewicz Numbers and Bipartite Ramsey Numbers

, 2016
15 ...
Collins, Alex F., Riasanovsky, Alexander W. N., Wallace, John C., Radziszowski, Stanis law P.   +3 more
openaire   +2 more sources

On Tournament Inversion

Journal of Graph Theory, Volume 110, Issue 1, Page 82-91, September 2025.
ABSTRACT An inversion of a tournament T is obtained by reversing the direction of all edges with both endpoints in some set of vertices. Let inv k ( T ) be the minimum length of a sequence of inversions using sets of size at most k that result in the transitive tournament.
Raphael Yuster
wiley   +1 more source