Selection on sperm size in response to promiscuity and variation in female sperm storage organs

Autor: Emily R. A. Cramer, Zelealem B. Yilma, Jan T. Lifjeld

Publikováno v: Journal of evolutionary biologyREFERENCES.

Sperm cells are exceptionally morphologically diverse across taxa. However, morphology can be quite uniform within species, particularly for species where females copulate with many males per reproductive bout. Strong sexual selection in these promis

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e8ea6484298d0b346eae56d2751bade8
https://pubmed.ncbi.nlm.nih.gov/36357998

The Erdős–Rothschild problem on edge-colourings with forbidden monochromatic cliques

Autor: Oleg Pikhurko, Zelealem B. Yilma, Katherine Staden

Let $\mathbf{k} := (k_1,\dots,k_s)$ be a sequence of natural numbers. For a graph $G$, let $F(G;\mathbf{k})$ denote the number of colourings of the edges of $G$ with colours $1,\dots,s$ such that, for every $c \in \{1,\dots,s\}$, the edges of colour

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https://doi.org/10.1017/s0305004116001031

Antimagic Properties of Graphs with Large Maximum Degree

Autor: Zelealem B. Yilma

Publikováno v: Journal of Graph Theory. 72:367-373

An antimagic labeling of a graph with m edges and n vertices is a bijection from the set of edges to the integers such that all n vertex sums are pairwise distinct, where a vertex sum is the sum of labels of all edges incident with the same vertex. A

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::ae87e7fc94d677793fc833fb6a362012
https://doi.org/10.1002/jgt.21664

Set Systems without a Strong Simplex

Autor: Zelealem B. Yilma, Oleg Pikhurko, Tao Jiang

Publikováno v: SIAM Journal on Discrete Mathematics. 24:1038-1045

A $d$-simplex is a collection of $d+1$ sets such that every $d$ of them have nonempty intersection and the intersection of all of them is empty. A strong $d$-simplex is a collection of $d+2$ sets $A,A_1,\dots,A_{d+1}$ such that $\{A_1,\dots,A_{d+1}\}

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https://doi.org/10.1137/090760775

A Tight Bound on the Set Chromatic Number

Autor: Jean-Sébastien Sereni, Zelealem B. Yilma

Publikováno v: Discussiones Mathematicae Graph Theory
Discussiones Mathematicae Graph Theory, University of Zielona Góra, 2013, 33 (2), pp.461--465. ⟨10.7151/dmgt.1679⟩
Discussiones Mathematicae Graph Theory, Vol 33, Iss 2, Pp 461-465 (2013)
Discussiones Mathematicae Graph Theory, 2013, 33 (2), pp.461--465. ⟨10.7151/dmgt.1679⟩

International audience; The purpose of this note is to provide a tight bound on the set chromatic number of a graph in terms of its chromatic number. Namely, for all graphs G, we show that χs(G) ≥ log2χ(G) + 1, where χs(G) and χ(G) are the set

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https://hal.archives-ouvertes.fr/hal-00624323v2/file/SeYi11.pdf